/* pngcp.c
*
* Copyright (c) 2016 John Cunningham Bowler
*
* Last changed in libpng 1.6.24 [August 4, 2016]
*
* This code is released under the libpng license.
* For conditions of distribution and use, see the disclaimer
* and license in png.h
*
* This is an example of copying a PNG without changes using the png_read_png
* and png_write_png interfaces. A considerable number of options are provided
* to manipulate the compression of the PNG data and other compressed chunks.
*
* For a more extensive example that uses the transforms see
* contrib/libtests/pngimage.c in the libpng distribution.
*/
#include "pnglibconf.h" /* To find how libpng was configured. */
#ifdef PNG_PNGCP_TIMING_SUPPORTED
/* WARNING:
*
* This test is here to allow POSIX.1b extensions to be used if enabled in
* the compile; specifically the code requires_POSIX_C_SOURCE support of
* 199309L or later to enable clock_gettime use.
*
* IF this causes problems THEN compile with a strict ANSI C compiler and let
* this code turn on the POSIX features that it minimally requires.
*
* IF this does not work there is probably a bug in your ANSI C compiler or
* your POSIX implementation.
*/
# define _POSIX_C_SOURCE 199309L
#else /* No timing support required */
# define _POSIX_SOURCE 1
#endif
#if defined(HAVE_CONFIG_H) && !defined(PNG_NO_CONFIG_H)
# include <config.h>
#endif
#include <stdio.h>
/* Define the following to use this test against your installed libpng, rather
* than the one being built here:
*/
#ifdef PNG_FREESTANDING_TESTS
# include <png.h>
#else
# include "../../png.h"
#endif
#if PNG_LIBPNG_VER < 10700
/* READ_PNG and WRITE_PNG were not defined, so: */
# ifdef PNG_INFO_IMAGE_SUPPORTED
# ifdef PNG_SEQUENTIAL_READ_SUPPORTED
# define PNG_READ_PNG_SUPPORTED
# endif /* SEQUENTIAL_READ */
# ifdef PNG_WRITE_SUPPORTED
# define PNG_WRITE_PNG_SUPPORTED
# endif /* WRITE */
# endif /* INFO_IMAGE */
#endif /* pre 1.7.0 */
#if (defined(PNG_READ_PNG_SUPPORTED)) && (defined(PNG_WRITE_PNG_SUPPORTED))
#include <stdarg.h>
#include <stdlib.h>
#include <string.h>
#include <errno.h>
#include <limits.h>
#include <assert.h>
#include <unistd.h>
#include <sys/stat.h>
#include <zlib.h>
#ifndef PNG_SETJMP_SUPPORTED
# include <setjmp.h> /* because png.h did *not* include this */
#endif
#ifdef __cplusplus
# define voidcast(type, value) static_cast<type>(value)
#else
# define voidcast(type, value) (value)
#endif /* __cplusplus */
#ifdef __GNUC__
/* Many versions of GCC erroneously report that local variables unmodified
* within the scope of a setjmp may be clobbered. This hacks round the
* problem (sometimes) without harming other compilers.
*/
# define gv volatile
#else
# define gv
#endif
/* 'CLOCK_PROCESS_CPUTIME_ID' is one of the clock timers for clock_gettime. It
* need not be supported even when clock_gettime is available. It returns the
* 'CPU' time the process has consumed. 'CPU' time is assumed to include time
* when the CPU is actually blocked by a pending cache fill but not time
* waiting for page faults. The attempt is to get a measure of the actual time
* the implementation takes to read a PNG ignoring the potentially very large IO
* overhead.
*/
#ifdef PNG_PNGCP_TIMING_SUPPORTED
# include <time.h> /* clock_gettime and associated definitions */
# ifndef CLOCK_PROCESS_CPUTIME_ID
/* Prevent inclusion of the spurious code: */
# undef PNG_PNGCP_TIMING_SUPPORTED
# endif
#endif /* PNGCP_TIMING */
/* So if the timing feature has been activated: */
/* This structure is used to control the test of a single file. */
typedef enum
{
VERBOSE, /* switches on all messages */
INFORMATION,
WARNINGS, /* switches on warnings */
LIBPNG_WARNING,
APP_WARNING,
ERRORS, /* just errors */
APP_FAIL, /* continuable error - no need to longjmp */
LIBPNG_ERROR, /* this and higher cause a longjmp */
LIBPNG_BUG, /* erroneous behavior in libpng */
APP_ERROR, /* such as out-of-memory in a callback */
QUIET, /* no normal messages */
USER_ERROR, /* such as file-not-found */
INTERNAL_ERROR
} error_level;
#define LEVEL_MASK 0xf /* where the level is in 'options' */
#define STRICT 0x010 /* Fail on warnings as well as errors */
#define LOG 0x020 /* Log pass/fail to stdout */
#define CONTINUE 0x040 /* Continue on APP_FAIL errors */
#define SIZES 0x080 /* Report input and output sizes */
#define SEARCH 0x100 /* Search IDAT compression options */
#define NOWRITE 0x200 /* Do not write an output file */
#ifdef PNG_CHECK_FOR_INVALID_INDEX_SUPPORTED
# define IGNORE_INDEX 0x400 /* Ignore out of range palette indices (BAD!) */
# ifdef PNG_GET_PALETTE_MAX_SUPPORTED
# define FIX_INDEX 0x800 /* 'Fix' out of range palette indices (OK) */
# endif /* GET_PALETTE_MAX */
#endif /* CHECK_FOR_INVALID_INDEX */
#define OPTION 0x80000000 /* Used for handling options */
#define LIST 0x80000001 /* Used for handling options */
/* Result masks apply to the result bits in the 'results' field below; these
* bits are simple 1U<<error_level. A pass requires either nothing worse than
* warnings (--relaxes) or nothing worse than information (--strict)
*/
#define RESULT_STRICT(r) (((r) & ~((1U<<WARNINGS)-1)) == 0)
#define RESULT_RELAXED(r) (((r) & ~((1U<<ERRORS)-1)) == 0)
/* OPTION DEFINITIONS */
static const char range_lo[] = "low";
static const char range_hi[] = "high";
static const char all[] = "all";
#define RANGE(lo,hi) { range_lo, lo }, { range_hi, hi }
typedef struct value_list
{
const char *name; /* the command line name of the value */
int value; /* the actual value to use */
} value_list;
static const value_list
#ifdef PNG_SW_COMPRESS_png_level
vl_compression[] =
{
/* Overall compression control. The order controls the search order for
* 'all'. Since the search is for the smallest the order used is low memory
* then high speed.
*/
{ "low-memory", PNG_COMPRESSION_LOW_MEMORY },
{ "high-speed", PNG_COMPRESSION_HIGH_SPEED },
{ "high-read-speed", PNG_COMPRESSION_HIGH_READ_SPEED },
{ "low", PNG_COMPRESSION_LOW },
{ "medium", PNG_COMPRESSION_MEDIUM },
{ "old", PNG_COMPRESSION_COMPAT },
{ "high", PNG_COMPRESSION_HIGH },
{ all, 0 }
},
#endif /* SW_COMPRESS_png_level */
#if defined(PNG_WRITE_CUSTOMIZE_COMPRESSION_SUPPORTED) ||\
defined(PNG_WRITE_CUSTOMIZE_ZTXT_COMPRESSION_SUPPORTED)
vl_strategy[] =
{
/* This controls the order of search. */
{ "huffman", Z_HUFFMAN_ONLY },
{ "RLE", Z_RLE },
{ "fixed", Z_FIXED }, /* the remainder do window searchs */
{ "filtered", Z_FILTERED },
{ "default", Z_DEFAULT_STRATEGY },
{ all, 0 }
},
#ifdef PNG_WRITE_CUSTOMIZE_ZTXT_COMPRESSION_SUPPORTED
vl_windowBits_text[] =
{
{ "default", MAX_WBITS/*from zlib*/ },
{ "minimum", 8 },
RANGE(8, MAX_WBITS/*from zlib*/),
{ all, 0 }
},
#endif /* text compression */
vl_level[] =
{
{ "default", Z_DEFAULT_COMPRESSION /* this is -1 */ },
{ "none", Z_NO_COMPRESSION },
{ "speed", Z_BEST_SPEED },
{ "best", Z_BEST_COMPRESSION },
{ "0", Z_NO_COMPRESSION },
RANGE(1, 9), /* this deliberately excludes '0' */
{ all, 0 }
},
vl_memLevel[] =
{
{ "max", MAX_MEM_LEVEL }, /* zlib maximum */
{ "1", 1 }, /* zlib minimum */
{ "default", 8 }, /* zlib default */
{ "2", 2 },
{ "3", 3 },
{ "4", 4 },
{ "5", 5 }, /* for explicit testing */
RANGE(6, MAX_MEM_LEVEL/*zlib*/), /* exclude 5 and below: zlib bugs */
{ all, 0 }
},
#endif /* WRITE_CUSTOMIZE_*COMPRESSION */
#ifdef PNG_WRITE_FILTER_SUPPORTED
vl_filter[] =
{
{ all, PNG_ALL_FILTERS },
{ "off", PNG_NO_FILTERS },
{ "none", PNG_FILTER_NONE },
{ "sub", PNG_FILTER_SUB },
{ "up", PNG_FILTER_UP },
{ "avg", PNG_FILTER_AVG },
{ "paeth", PNG_FILTER_PAETH }
},
#endif /* WRITE_FILTER */
#ifdef PNG_PNGCP_TIMING_SUPPORTED
# define PNGCP_TIME_READ 1
# define PNGCP_TIME_WRITE 2
vl_time[] =
{
{ "both", PNGCP_TIME_READ+PNGCP_TIME_WRITE },
{ "off", 0 },
{ "read", PNGCP_TIME_READ },
{ "write", PNGCP_TIME_WRITE }
},
#endif /* PNGCP_TIMING */
vl_IDAT_size[] = /* for png_set_IDAT_size */
{
{ "default", 0x7FFFFFFF },
{ "minimal", 1 },
RANGE(1, 0x7FFFFFFF)
},
#ifndef PNG_SW_IDAT_size
/* Pre 1.7 API: */
# define png_set_IDAT_size(p,v) png_set_compression_buffer_size(p, v)
#endif /* !SW_IDAT_size */
#define SL 8 /* stack limit in display, below */
vl_log_depth[] = { { "on", 1 }, { "off", 0 }, RANGE(0, SL) },
vl_on_off[] = { { "on", 1 }, { "off", 0 } };
#ifdef PNG_WRITE_CUSTOMIZE_COMPRESSION_SUPPORTED
static value_list
vl_windowBits_IDAT[] =
{
{ "default", MAX_WBITS },
{ "small", 9 },
RANGE(8, MAX_WBITS), /* modified by set_windowBits_hi */
{ all, 0 }
};
#endif /* IDAT compression */
typedef struct option
{
const char *name; /* name of the option */
png_uint_32 opt; /* an option, or OPTION or LIST */
png_byte search; /* Search on --search */
png_byte value_count; /* length of the list of values: */
const value_list *values; /* values for OPTION or LIST */
} option;
static const option options[] =
{
/* struct display options, these are set when the command line is read */
# define S(n,v) { #n, v, 0, 2, vl_on_off },
S(verbose, VERBOSE)
S(warnings, WARNINGS)
S(errors, ERRORS)
S(quiet, QUIET)
S(strict, STRICT)
S(log, LOG)
S(continue, CONTINUE)
S(sizes, SIZES)
S(search, SEARCH)
S(nowrite, NOWRITE)
# ifdef IGNORE_INDEX
S(ignore-palette-index, IGNORE_INDEX)
# endif /* IGNORE_INDEX */
# ifdef FIX_INDEX
S(fix-palette-index, FIX_INDEX)
# endif /* FIX_INDEX */
# undef S
/* OPTION settings, these and LIST settings are read on demand */
# define VLNAME(name) vl_ ## name
# define VLSIZE(name) voidcast(png_byte,\
(sizeof VLNAME(name))/(sizeof VLNAME(name)[0]))
# define VL(oname, name, type, search)\
{ oname, type, search, VLSIZE(name), VLNAME(name) },
# define VLO(oname, name, search) VL(oname, name, OPTION, search)
# ifdef PNG_WRITE_CUSTOMIZE_COMPRESSION_SUPPORTED
# define VLCIDAT(name) VLO(#name, name, 1/*search*/)
# ifdef PNG_SW_COMPRESS_level
# define VLCiCCP(name) VLO("ICC-profile-" #name, name, 0/*search*/)
# else
# define VLCiCCP(name)
# endif
# else
# define VLCIDAT(name)
# define VLCiCCP(name)
# endif /* WRITE_CUSTOMIZE_COMPRESSION */
# ifdef PNG_WRITE_CUSTOMIZE_ZTXT_COMPRESSION_SUPPORTED
# define VLCzTXt(name) VLO("text-" #name, name, 0/*search*/)
# else
# define VLCzTXt(name)
# endif /* WRITE_CUSTOMIZE_ZTXT_COMPRESSION */
# define VLC(name) VLCIDAT(name) VLCiCCP(name) VLCzTXt(name)
# ifdef PNG_SW_COMPRESS_png_level
/* The libpng compression level isn't searched beause it justs sets the
* other things that are searched!
*/
VLO("compression", compression, 0)
VLO("text-compression", compression, 0)
VLO("ICC-profile-compression", compression, 0)
# endif /* SW_COMPRESS_png_level */
VLC(strategy)
VLO("windowBits", windowBits_IDAT, 1)
# ifdef PNG_SW_COMPRESS_windowBits
VLO("ICC-profile-windowBits", windowBits_text/*sic*/, 0)
# endif
VLO("text-windowBits", windowBits_text, 0)
VLC(level)
VLC(memLevel)
VLO("IDAT-size", IDAT_size, 0)
VLO("log-depth", log_depth, 0)
# undef VLO
/* LIST settings */
# define VLL(name, search) VL(#name, name, LIST, search)
#ifdef PNG_WRITE_FILTER_SUPPORTED
VLL(filter, 0)
#endif /* WRITE_FILTER */
#ifdef PNG_PNGCP_TIMING_SUPPORTED
VLL(time, 0)
#endif /* PNGCP_TIMING */
# undef VLL
# undef VL
};
#ifdef __cplusplus
static const size_t option_count((sizeof options)/(sizeof options[0]));
#else /* !__cplusplus */
# define option_count ((sizeof options)/(sizeof options[0]))
#endif /* !__cplusplus */
static const char *
cts(int ct)
{
switch (ct)
{
case PNG_COLOR_TYPE_PALETTE: return "P";
case PNG_COLOR_TYPE_GRAY: return "G";
case PNG_COLOR_TYPE_GRAY_ALPHA: return "GA";
case PNG_COLOR_TYPE_RGB: return "RGB";
case PNG_COLOR_TYPE_RGB_ALPHA: return "RGBA";
default: return "INVALID";
}
}
struct display
{
jmp_buf error_return; /* Where to go to on error */
unsigned int errset; /* error_return is set */
const char *operation; /* What is happening */
const char *filename; /* The name of the original file */
const char *output_file; /* The name of the output file */
/* Used on both read and write: */
FILE *fp;
/* Used on a read, both the original read and when validating a written
* image.
*/
png_alloc_size_t read_size;
png_structp read_pp;
png_infop ip;
# if PNG_LIBPNG_VER < 10700 && defined PNG_TEXT_SUPPORTED
png_textp text_ptr; /* stash of text chunks */
int num_text;
int text_stashed;
# endif /* pre 1.7 */
# ifdef PNG_PNGCP_TIMING_SUPPORTED
struct timespec read_time;
struct timespec read_time_total;
struct timespec write_time;
struct timespec write_time_total;
# endif /* PNGCP_TIMING */
/* Used to write a new image (the original info_ptr is used) */
# define MAX_SIZE ((png_alloc_size_t)(-1))
png_alloc_size_t write_size;
png_alloc_size_t best_size;
png_structp write_pp;
/* Base file information */
png_alloc_size_t size;
png_uint_32 w;
png_uint_32 h;
int bpp;
png_byte ct;
int no_warnings; /* Do not output libpng warnings */
int min_windowBits; /* The windowBits range is 8..8 */
/* Options handling */
png_uint_32 results; /* A mask of errors seen */
png_uint_32 options; /* See display_log below */
png_byte entry[option_count]; /* The selected entry+1 of an option
* that appears on the command line, or
* 0 if it was not given. */
int value[option_count]; /* Corresponding value */
/* Compression exhaustive testing */
/* Temporary variables used only while testing a single collection of
* settings:
*/
unsigned int csp; /* next stack entry to use */
unsigned int nsp; /* highest active entry+1 found so far */
/* Values used while iterating through all the combinations of settings for a
* single file:
*/
unsigned int tsp; /* nsp from the last run; this is the
* index+1 of the highest active entry on
* this run; this entry will be advanced.
*/
int opt_string_start; /* Position in buffer for the first
* searched option; non-zero if earlier
* options were set on the command line.
*/
struct stack
{
png_alloc_size_t best_size; /* Best so far for this option */
png_alloc_size_t lo_size;
png_alloc_size_t hi_size;
int lo, hi; /* For binary chop of a range */
int best_val; /* Best value found so far */
int opt_string_end; /* End of the option string in 'curr' */
png_byte opt; /* The option being tested */
png_byte entry; /* The next value entry to be tested */
png_byte end; /* This is the last entry */
} stack[SL]; /* Stack of entries being tested */
char curr[32*SL]; /* current options being tested */
char best[32*SL]; /* best options */
char namebuf[FILENAME_MAX]; /* output file name */
};
static void
display_init(struct display *dp)
/* Call this only once right at the start to initialize the control
* structure, the (struct buffer) lists are maintained across calls - the
* memory is not freed.
*/
{
memset(dp, 0, sizeof *dp);
dp->operation = "internal error";
dp->filename = "command line";
dp->output_file = "no output file";
dp->options = WARNINGS; /* default to !verbose, !quiet */
dp->fp = NULL;
dp->read_pp = NULL;
dp->ip = NULL;
dp->write_pp = NULL;
dp->min_windowBits = -1; /* this is an OPTIND, so -1 won't match anything */
# if PNG_LIBPNG_VER < 10700 && defined PNG_TEXT_SUPPORTED
dp->text_ptr = NULL;
dp->num_text = 0;
dp->text_stashed = 0;
# endif /* pre 1.7 */
}
static void
display_clean_read(struct display *dp)
{
if (dp->read_pp != NULL)
png_destroy_read_struct(&dp->read_pp, NULL, NULL);
if (dp->fp != NULL)
{
FILE *fp = dp->fp;
dp->fp = NULL;
(void)fclose(fp);
}
}
static void
display_clean_write(struct display *dp)
{
if (dp->fp != NULL)
{
FILE *fp = dp->fp;
dp->fp = NULL;
(void)fclose(fp);
}
if (dp->write_pp != NULL)
png_destroy_write_struct(&dp->write_pp, dp->tsp > 0 ? NULL : &dp->ip);
}
static void
display_clean(struct display *dp)
{
display_clean_read(dp);
display_clean_write(dp);
dp->output_file = NULL;
# if PNG_LIBPNG_VER < 10700 && defined PNG_TEXT_SUPPORTED
/* This is actually created and used by the write code, but only
* once; it has to be retained for subsequent writes of the same file.
*/
if (dp->text_stashed)
{
dp->text_stashed = 0;
dp->num_text = 0;
free(dp->text_ptr);
dp->text_ptr = NULL;
}
# endif /* pre 1.7 */
/* leave the filename for error detection */
dp->results = 0; /* reset for next time */
}
static void
display_destroy(struct display *dp)
{
/* Release any memory held in the display. */
display_clean(dp);
}
static struct display *
get_dp(png_structp pp)
/* The display pointer is always stored in the png_struct error pointer */
{
struct display *dp = (struct display*)png_get_error_ptr(pp);
if (dp == NULL)
{
fprintf(stderr, "pngcp: internal error (no display)\n");
exit(99); /* prevents a crash */
}
return dp;
}
/* error handling */
#ifdef __GNUC__
# define VGATTR __attribute__((__format__ (__printf__,3,4)))
/* Required to quiet GNUC warnings when the compiler sees a stdarg function
* that calls one of the stdio v APIs.
*/
#else
# define VGATTR
#endif
static void VGATTR
display_log(struct display *dp, error_level level, const char *fmt, ...)
/* 'level' is as above, fmt is a stdio style format string. This routine
* does not return if level is above LIBPNG_WARNING
*/
{
dp->results |= 1U << level;
if (level > (error_level)(dp->options & LEVEL_MASK))
{
const char *lp;
va_list ap;
switch (level)
{
case INFORMATION: lp = "information"; break;
case LIBPNG_WARNING: lp = "warning(libpng)"; break;
case APP_WARNING: lp = "warning(pngcp)"; break;
case APP_FAIL: lp = "error(continuable)"; break;
case LIBPNG_ERROR: lp = "error(libpng)"; break;
case LIBPNG_BUG: lp = "bug(libpng)"; break;
case APP_ERROR: lp = "error(pngcp)"; break;
case USER_ERROR: lp = "error(user)"; break;
case INTERNAL_ERROR: /* anything unexpected is an internal error: */
case VERBOSE: case WARNINGS: case ERRORS: case QUIET:
default: lp = "bug(pngcp)"; break;
}
fprintf(stderr, "%s: %s: %s",
dp->filename != NULL ? dp->filename : "<stdin>", lp, dp->operation);
fprintf(stderr, ": ");
va_start(ap, fmt);
vfprintf(stderr, fmt, ap);
va_end(ap);
fputc('\n', stderr);
}
/* else do not output any message */
/* Errors cause this routine to exit to the fail code */
if (level > APP_FAIL || (level > ERRORS && !(dp->options & CONTINUE)))
{
if (dp->errset)
longjmp(dp->error_return, level);
else
exit(99);
}
}
#if PNG_LIBPNG_VER < 10700 && defined PNG_TEXT_SUPPORTED
static void
text_stash(struct display *dp)
{
/* libpng 1.6 and earlier fixed a bug whereby text chunks were written
* multiple times by png_write_png; the issue was that png_write_png passed
* the same png_info to both png_write_info and png_write_end. Rather than
* fixing it by recording the information in the png_struct, or by recording
* where to write the chunks, the fix made was to change the 'compression'
* field of the chunk to invalid values, rendering the png_info somewhat
* useless.
*
* The only fix for this given that we use the png_info more than once is to
* make a copy of the text chunks and png_set_text it each time. This adds a
* text chunks, so they get replicated, but only the new set gets written
* each time. This uses memory like crazy but there is no way to delete the
* useless chunks from the png_info.
*
* To make this slightly more efficient only the top level structure is
* copied; since the old strings are actually preserved (in 1.6 and earlier)
* this happens to work.
*/
png_textp chunks = NULL;
dp->num_text = png_get_text(dp->write_pp, dp->ip, &chunks, NULL);
if (dp->num_text > 0)
{
dp->text_ptr = voidcast(png_textp, malloc(dp->num_text * sizeof *chunks));
if (dp->text_ptr == NULL)
display_log(dp, APP_ERROR, "text chunks: stash malloc failed");
else
memcpy(dp->text_ptr, chunks, dp->num_text * sizeof *chunks);
}
dp->text_stashed = 1; /* regardless of whether there are chunks or not */
}
#define text_stash(dp) if (!dp->text_stashed) text_stash(dp)
static void
text_restore(struct display *dp)
{
/* libpng makes a copy, so this is fine: */
if (dp->text_ptr != NULL)
png_set_text(dp->write_pp, dp->ip, dp->text_ptr, dp->num_text);
}
#define text_restore(dp) if (dp->text_stashed) text_restore(dp)
#else
#define text_stash(dp) ((void)0)
#define text_restore(dp) ((void)0)
#endif /* pre 1.7 */
/* OPTIONS:
*
* The command handles options of the forms:
*
* --option
* Turn an option on (Option)
* --no-option
* Turn an option off (Option)
* --option=value
* Set an option to a value (Value)
* --option=val1,val2,val3
* Set an option to a bitmask constructed from the values (List)
*/
static png_byte
option_index(struct display *dp, const char *opt, size_t len)
/* Return the index (in options[]) of the given option, outputs an error if
* it does not exist. Takes the name of the option and a length (number of
* characters in the name).
*/
{
png_byte j;
for (j=0; j<option_count; ++j)
if (strncmp(options[j].name, opt, len) == 0 && options[j].name[len] == 0)
return j;
/* If the setjmp buffer is set the code is asking for an option index; this
* is bad. Otherwise this is the command line option parsing.
*/
display_log(dp, dp->errset ? INTERNAL_ERROR : USER_ERROR,
"%.*s: unknown option", (int)/*SAFE*/len, opt);
abort(); /* NOT REACHED */
}
/* This works for an option name (no quotes): */
#define OPTIND(dp, name) option_index(dp, #name, (sizeof #name)-1)
static int
get_option(struct display *dp, const char *opt, int *value)
{
const png_byte i = option_index(dp, opt, strlen(opt));
if (dp->entry[i]) /* option was set on command line */
{
*value = dp->value[i];
return 1;
}
else
return 0;
}
static int
set_opt_string_(struct display *dp, unsigned int sp, png_byte opt,
const char *entry_name)
/* Add the appropriate option string to dp->curr. */
{
int offset, add;
if (sp > 0)
offset = dp->stack[sp-1].opt_string_end;
else
offset = dp->opt_string_start;
if (entry_name == range_lo)
add = sprintf(dp->curr+offset, " --%s=%d", options[opt].name,
dp->value[opt]);
else
add = sprintf(dp->curr+offset, " --%s=%s", options[opt].name, entry_name);
if (add < 0)
display_log(dp, INTERNAL_ERROR, "sprintf failed");
assert(offset+add < (int)/*SAFE*/sizeof dp->curr);
return offset+add;
}
static void
set_opt_string(struct display *dp, unsigned int sp)
/* Add the appropriate option string to dp->curr. */
{
dp->stack[sp].opt_string_end = set_opt_string_(dp, sp, dp->stack[sp].opt,
options[dp->stack[sp].opt].values[dp->stack[sp].entry].name);
}
static void
record_opt(struct display *dp, png_byte opt, const char *entry_name)
/* Record this option in dp->curr; called for an option not being searched,
* the caller passes in the name of the value, or range_lo to use the
* numerical value.
*/
{
const unsigned int sp = dp->csp; /* stack entry of next searched option */
if (sp >= dp->tsp)
{
/* At top of stack; add the opt string for this entry to the previous
* searched entry or the start of the dp->curr buffer if there is nothing
* on the stack yet (sp == 0).
*/
const int offset = set_opt_string_(dp, sp, opt, entry_name);
if (sp > 0)
dp->stack[sp-1].opt_string_end = offset;
else
dp->opt_string_start = offset;
}
/* else do nothing: option already recorded */
}
static int
opt_list_end(struct display *dp, png_byte opt, png_byte entry)
{
if (options[opt].values[entry].name == range_lo)
return entry+1U >= options[opt].value_count /* missing range_hi */ ||
options[opt].values[entry+1U].name != range_hi /* likewise */ ||
options[opt].values[entry+1U].value <= dp->value[opt] /* range end */;
else
return entry+1U >= options[opt].value_count /* missing 'all' */ ||
options[opt].values[entry+1U].name == all /* last entry */;
}
static void
push_opt(struct display *dp, unsigned int sp, png_byte opt, int search)
/* Push a new option onto the stack, initializing the new stack entry
* appropriately; this does all the work of next_opt (setting end/nsp) for
* the first entry in the list.
*/
{
png_byte entry;
const char *entry_name;
assert(sp == dp->tsp && sp < SL);
/* The starting entry is entry 0 unless there is a range in which case it is
* the entry corresponding to range_lo:
*/
entry = options[opt].value_count;
assert(entry > 0U);
do
{
entry_name = options[opt].values[--entry].name;
if (entry_name == range_lo)
break;
}
while (entry > 0U);
dp->tsp = sp+1U;
dp->stack[sp].best_size =
dp->stack[sp].lo_size =
dp->stack[sp].hi_size = MAX_SIZE;
if (search && entry_name == range_lo) /* search this range */
{
dp->stack[sp].lo = options[opt].values[entry].value;
/* check for a mal-formed RANGE above: */
assert(entry+1 < options[opt].value_count &&
options[opt].values[entry+1].name == range_hi);
dp->stack[sp].hi = options[opt].values[entry+1].value;
}
else
{
/* next_opt will just iterate over the range. */
dp->stack[sp].lo = INT_MAX;
dp->stack[sp].hi = INT_MIN; /* Prevent range chop */
}
dp->stack[sp].opt = opt;
dp->stack[sp].entry = entry;
dp->stack[sp].best_val = dp->value[opt] = options[opt].values[entry].value;
set_opt_string(dp, sp);
/* This works for the search case too; if the range has only one entry 'end'
* will be marked here.
*/
if (opt_list_end(dp, opt, entry))
{
dp->stack[sp].end = 1;
/* Skip the warning if pngcp did this itself. See the code in
* set_windowBits_hi.
*/
if (opt != dp->min_windowBits)
display_log(dp, APP_WARNING, "%s: only testing one value",
options[opt].name);
}
else
{
dp->stack[sp].end = 0;
dp->nsp = dp->tsp;
}
/* Do a lazy cache of the text chunks for libpng 1.6 and earlier; this is
* because they can only be written once(!) so if we are going to re-use the
* png_info we need a copy.
*/
text_stash(dp);
}
static void
next_opt(struct display *dp, unsigned int sp)
/* Return the next value for this option. When called 'sp' is expected to be
* the topmost stack entry - only the topmost entry changes each time round -
* and there must be a valid entry to return. next_opt will set dp->nsp to
* sp+1 if more entries are available, otherwise it will not change it and
* set dp->stack[s].end to true.
*/
{
int search = 0;
png_byte entry, opt;
const char *entry_name;
/* dp->stack[sp] must be the top stack entry and it must be active: */
assert(sp+1U == dp->tsp && !dp->stack[sp].end);
opt = dp->stack[sp].opt;
entry = dp->stack[sp].entry;
assert(entry+1U < options[opt].value_count);
entry_name = options[opt].values[entry].name;
assert(entry_name != NULL);
/* For ranges increment the value but don't change the entry, for all other
* cases move to the next entry and load its value:
*/
if (entry_name == range_lo) /* a range */
{
/* A range can be iterated over or searched. The default iteration option
* is indicated by hi < lo on the stack, otherwise the range being search
* is [lo..hi] (inclusive).
*/
if (dp->stack[sp].lo > dp->stack[sp].hi)
dp->value[opt]++;
else
{
/* This is the best size found for this option value: */
png_alloc_size_t best_size = dp->stack[sp].best_size;
int lo = dp->stack[sp].lo;
int hi = dp->stack[sp].hi;
int val = dp->value[opt];
search = 1; /* end is determined here */
assert(best_size < MAX_SIZE);
if (val == lo)
{
/* Finding the best for the low end of the range: */
dp->stack[sp].lo_size = best_size;
assert(hi > val);
if (hi == val+1) /* only 2 entries */
dp->stack[sp].end = 1;
val = hi;
}
else if (val == hi)
{
dp->stack[sp].hi_size = best_size;
assert(val > lo+1); /* else 'end' set above */
if (val == lo+2) /* only three entries to test */
dp->stack[sp].end = 1;
val = (lo + val)/2;
}
else
{
png_alloc_size_t lo_size = dp->stack[sp].lo_size;
png_alloc_size_t hi_size = dp->stack[sp].hi_size;
/* lo and hi should have been tested. */
assert(lo_size < MAX_SIZE && hi_size < MAX_SIZE);
/* These cases arise with the 'probe' handling below when there is a
* dip or peak in the size curve.
*/
if (val < lo) /* probing a new lo */
{
/* Swap lo and val: */
dp->stack[sp].lo = val;
dp->stack[sp].lo_size = best_size;
val = lo;
best_size = lo_size;
lo = dp->stack[sp].lo;
lo_size = dp->stack[sp].lo_size;
}
else if (val > hi) /* probing a new hi */
{
/* Swap hi and val: */
dp->stack[sp].hi = val;
dp->stack[sp].hi_size = best_size;
val = hi;
best_size = hi_size;
hi = dp->stack[sp].hi;
hi_size = dp->stack[sp].hi_size;
}
/* The following should be true or something got messed up above. */
assert(lo < val && val < hi);
/* If there are only four entries (lo, val, hi plus one more) just
* test the remaining entry.
*/
if (hi == lo+3)
{
/* Because of the 'probe' code val can either be lo+1 or hi-1; we
* need to test the other.
*/
val = lo + ((val == lo+1) ? 2 : 1);
assert(lo < val && val < hi);
dp->stack[sp].end = 1;
}
else
{
/* There are at least 2 entries still untested between lo and hi,
* i.e. hi >= lo+4. 'val' is the midpoint +/- 0.5
*
* Separate out the four easy cases when lo..val..hi are
* monotonically decreased or (more weird) increasing:
*/
assert(hi > lo+3);
if (lo_size <= best_size && best_size <= hi_size)
{
/* Select the low range; testing this first favours the low
* range over the high range when everything comes out equal.
* Because of the probing 'val' may be lo+1. In that case end
* the search and set 'val' to lo+2.
*/
if (val == lo+1)
{
++val;
dp->stack[sp].end = 1;
}
else
{
dp->stack[sp].hi = hi = val;
dp->stack[sp].hi_size = best_size;
val = (lo + val) / 2;
}
}
else if (lo_size >= best_size && best_size >= hi_size)
{
/* Monotonically decreasing size; this is the expected case.
* Select the high end of the range. As above, val may be
* hi-1.
*/
if (val == hi-1)
{
--val;
dp->stack[sp].end = 1;
}
else
{
dp->stack[sp].lo = lo = val;
dp->stack[sp].lo_size = best_size;
val = (val + hi) / 2;
}
}
/* If both those tests failed 'best_size' is either greater than
* or less than both lo_size and hi_size. There is a peak or dip
* in the curve of sizes from lo to hi and val is on the peak or
* dip.
*
* Because the ranges being searched as so small (level is 1..9,
* windowBits 8..15, memLevel 1..9) there will only be at most
* three untested values between lo..val and val..hi, so solve
* the problem by probing down from hi or up from lo, whichever
* is the higher.
*
* This is the place where 'val' is set to outside the range
* lo..hi, described as 'probing', though maybe 'narrowing' would
* be more accurate.
*/
else if (lo_size <= hi_size) /* down from hi */
{
dp->stack[sp].hi = val;
dp->stack[sp].hi_size = best_size;
val = --hi;
}
else /* up from low */
{
dp->stack[sp].lo = val;
dp->stack[sp].lo_size = best_size;
val = ++lo;
}
/* lo and hi are still the true range limits, check for the end
* condition.
*/
assert(hi > lo+1);
if (hi <= lo+2)
dp->stack[sp].end = 1;
}
}
assert(val != dp->stack[sp].best_val); /* should be a new value */
dp->value[opt] = val;
dp->stack[sp].best_size = MAX_SIZE;
}
}
else
{
/* Increment 'entry' */
dp->value[opt] = options[opt].values[++entry].value;
dp->stack[sp].entry = entry;
}
set_opt_string(dp, sp);
if (!search && opt_list_end(dp, opt, entry)) /* end of list */
dp->stack[sp].end = 1;
else if (!dp->stack[sp].end) /* still active after all these tests */
dp->nsp = dp->tsp;
}
static int
compare_option(const struct display *dp, unsigned int sp)
{
int opt = dp->stack[sp].opt;
/* If the best so far is numerically less than the current value the
* current set of options is invariably worse.
*/
if (dp->stack[sp].best_val < dp->value[opt])
return -1;
/* Lists of options are searched out of numerical order (currently only
* strategy), so only return +1 here when a range is being searched.
*/
else if (dp->stack[sp].best_val > dp->value[opt])
{
if (dp->stack[sp].lo <= dp->stack[sp].hi /*searching*/)
return 1;
else
return -1;
}
else
return 0; /* match; current value is the best one */
}
static int
advance_opt(struct display *dp, png_byte opt, int search)
{
unsigned int sp = dp->csp++; /* my stack entry */
assert(sp >= dp->nsp); /* nsp starts off zero */
/* If the entry was active in the previous run dp->stack[sp] is already
* set up and dp->tsp will be greater than sp, otherwise a new entry
* needs to be created.
*
* dp->nsp is handled this way:
*
* 1) When an option is pushed onto the stack dp->nsp and dp->tsp are
* both set (by push_opt) to the next stack entry *unless* there is
* only one entry in the new list, in which case dp->stack[sp].end
* is set.
*
* 2) For the top stack entry next_opt is called. The entry must be
* active (dp->stack[sp].end is not set) and either 'nsp' or 'end'
* will be updated as appropriate.
*
* 3) For lower stack entries nsp is set unless the stack entry is
* already at the end. This means that when all the higher entries
* are popped this entry will be too.
*/
if (sp >= dp->tsp)
{
push_opt(dp, sp, opt, search); /* This sets tsp to sp+1 */
return 1; /* initialized */
}
else
{
int ret = 0; /* unchanged */
/* An option that is already on the stack; update best_size and best_val
* if appropriate. On the first run there are no previous values and
* dp->write_size will be MAX_SIZE, however on the first run dp->tsp
* starts off as 0.
*/
assert(dp->write_size > 0U && dp->write_size < MAX_SIZE);
if (dp->stack[sp].best_size > dp->write_size ||
(dp->stack[sp].best_size == dp->write_size &&
compare_option(dp, sp) > 0))
{
dp->stack[sp].best_size = dp->write_size;
dp->stack[sp].best_val = dp->value[opt];
}
if (sp+1U >= dp->tsp)
{
next_opt(dp, sp);
ret = 1; /* advanced */
}
else if (!dp->stack[sp].end) /* Active, not at top of stack */
dp->nsp = sp+1U;
return ret; /* advanced || unchanged */
}
}
static int
getallopts_(struct display *dp, const png_byte opt, int *value, int record)
/* Like getop but iterate over all the values if the option was set to "all".
*/
{
if (dp->entry[opt]) /* option was set on command line */
{
/* Simple, single value, entries don't have a stack frame and have a fixed
* value (it doesn't change once set on the command line). Otherwise the
* value (entry) selected from the command line is 'all':
*/
const char *entry_name = options[opt].values[dp->entry[opt]-1].name;
if (entry_name == all)
(void)advance_opt(dp, opt, 0/*do not search; iterate*/);
else if (record)
record_opt(dp, opt, entry_name);
*value = dp->value[opt];
return 1; /* set */
}
else
return 0; /* not set */
}
static int
getallopts(struct display *dp, const char *opt_str, int *value)
{
return getallopts_(dp, option_index(dp, opt_str, strlen(opt_str)), value, 0);
}
static int
getsearchopts(struct display *dp, const char *opt_str, int *value)
/* As above except that if the option was not set try a search */
{
png_byte istrat;
const png_byte opt = option_index(dp, opt_str, strlen(opt_str));
int record = options[opt].search;
const char *entry_name;
/* If it was set on the command line honour the setting, including 'all'
* which will override the built in search:
*/
if (getallopts_(dp, opt, value, record))
return 1;
else if (!record) /* not a search option */
return 0; /* unset and not searched */
/* Otherwise decide what to do here. */
istrat = OPTIND(dp, strategy);
entry_name = range_lo; /* record the value, not the name */
if (opt == istrat) /* search all strategies */
(void)advance_opt(dp, opt, 0/*iterate*/), record=0;
else if (opt == OPTIND(dp, level))
{
/* Both RLE and HUFFMAN don't benefit from level increases */
if (dp->value[istrat] == Z_RLE || dp->value[istrat] == Z_HUFFMAN_ONLY)
dp->value[opt] = 1;
else /* fixed, filtered or default */
(void)advance_opt(dp, opt, 1/*search*/), record=0;
}
else if (opt == OPTIND(dp, windowBits))
{
/* Changing windowBits for strategies that do not search the window is
* pointless. Huffman-only does not search, RLE only searches backwards
* one byte, so given that the maximum string length is 258, a windowBits
* of 9 is always sufficient.
*/
if (dp->value[istrat] == Z_HUFFMAN_ONLY)
dp->value[opt] = 8;
else if (dp->value[istrat] == Z_RLE)
dp->value[opt] = 9;
else /* fixed, filtered or default */
(void)advance_opt(dp, opt, 1/*search*/), record=0;
}
else if (opt == OPTIND(dp, memLevel))
{
# if 0
(void)advance_opt(dp, opt, 0/*all*/), record=0;
# else
dp->value[opt] = MAX_MEM_LEVEL;
# endif
}
else /* something else */
assert(0=="reached");
if (record)
record_opt(dp, opt, entry_name);
/* One of the above searched options: */
*value = dp->value[opt];
return 1;
}
static int
find_val(struct display *dp, png_byte opt, const char *str, size_t len)
/* Like option_index but sets (index+i) of the entry in options[opt] that
* matches str[0..len-1] into dp->entry[opt] as well as returning the actual
* value.
*/
{
int rlo = INT_MAX, rhi = INT_MIN;
png_byte j, irange = 0;
for (j=1U; j<=options[opt].value_count; ++j)
{
if (strncmp(options[opt].values[j-1U].name, str, len) == 0 &&
options[opt].values[j-1U].name[len] == 0)
{
dp->entry[opt] = j;
return options[opt].values[j-1U].value;
}
else if (options[opt].values[j-1U].name == range_lo)
rlo = options[opt].values[j-1U].value, irange = j;
else if (options[opt].values[j-1U].name == range_hi)
rhi = options[opt].values[j-1U].value;
}
/* No match on the name, but there may be a range. */
if (irange > 0)
{
char *ep = NULL;
long l = strtol(str, &ep, 0);
if (ep == str+len && l >= rlo && l <= rhi)
{
dp->entry[opt] = irange; /* range_lo */
return (int)/*SAFE*/l;
}
}
display_log(dp, dp->errset ? INTERNAL_ERROR : USER_ERROR,
"%s: unknown value setting '%.*s'", options[opt].name,
(int)/*SAFE*/len, str);
abort(); /* NOT REACHED */
}
static int
opt_check(struct display *dp, const char *arg)
{
assert(dp->errset == 0);
if (arg != NULL && arg[0] == '-' && arg[1] == '-')
{
int i = 0, negate = (strncmp(arg+2, "no-", 3) == 0), val;
png_byte j;
if (negate)
arg += 5; /* --no- */
else
arg += 2; /* -- */
/* Find the length (expect arg\0 or arg=) */
while (arg[i] != 0 && arg[i] != '=') ++i;
/* So arg[0..i-1] is the argument name, this does not return if this isn't
* a valid option name.
*/
j = option_index(dp, arg, i);
/* It matcheth an option; check the remainder. */
if (arg[i] == 0) /* no specified value, use the default */
{
val = options[j].values[negate].value;
dp->entry[j] = (png_byte)/*SAFE*/(negate + 1U);
}
else
{
const char *list = arg + (i+1);
/* Expect a single value here unless this is a list, in which case
* multiple values are combined.
*/
if (options[j].opt != LIST)
{
/* find_val sets 'dp->entry[j]' to a non-zero value: */
val = find_val(dp, j, list, strlen(list));
if (negate)
{
if (options[j].opt < OPTION)
val = !val;
else
{
display_log(dp, USER_ERROR,
"%.*s: option=arg cannot be negated", i, arg);
abort(); /* NOT REACHED */
}
}
}
else /* multiple options separated by ',' characters */
{
/* --no-option negates list values from the default, which should
* therefore be 'all'. Notice that if the option list is empty in
* this case nothing will be removed and therefore --no-option= is
* the same as --option.
*/
if (negate)
val = options[j].values[0].value;
else
val = 0;
while (*list != 0) /* allows option= which sets 0 */
{
/* A value is terminated by the end of the list or a ','
* character.
*/
int v, iv;
iv = 0; /* an index into 'list' */
while (list[++iv] != 0 && list[iv] != ',') {}
v = find_val(dp, j, list, iv);
if (negate)
val &= ~v;
else
val |= v;
list += iv;
if (*list != 0)
++list; /* skip the ',' */
}
}
}
/* 'val' is the new value, store it for use later and debugging: */
dp->value[j] = val;
if (options[j].opt < LEVEL_MASK)
{
/* The handling for error levels is to set the level. */
if (val) /* Set this level */
dp->options = (dp->options & ~LEVEL_MASK) | options[j].opt;
else
display_log(dp, USER_ERROR,
"%.*s: messages cannot be turned off individually; set a message level",
i, arg);
}
else if (options[j].opt < OPTION)
{
if (val)
dp->options |= options[j].opt;
else
dp->options &= ~options[j].opt;
}
return 1; /* this is an option */
}
else
return 0; /* not an option */
}
#ifdef PNG_PNGCP_TIMING_SUPPORTED
static void
set_timer(struct display *dp, struct timespec *timer)
{
/* Do the timing using clock_gettime and the per-process timer. */
if (clock_gettime(CLOCK_PROCESS_CPUTIME_ID, timer))
{
display_log(dp, APP_ERROR,
"CLOCK_PROCESS_CPUTIME_ID: %s: timing disabled\n", strerror(errno));
dp->value[OPTIND(dp,time)] = 0; /* i.e. off */
}
}
static void
start_timer(struct display *dp, int what)
{
if ((dp->value[OPTIND(dp,time)] & what) != 0)
set_timer(dp, what == PNGCP_TIME_READ ? &dp->read_time : &dp->write_time);
}
static void
end_timer(struct display *dp, int what)
{
if ((dp->value[OPTIND(dp,time)] & what) != 0)
{
struct timespec t, tmp;
set_timer(dp, &t);
if (what == PNGCP_TIME_READ)
tmp = dp->read_time;
else
tmp = dp->write_time;
t.tv_sec -= tmp.tv_sec;
t.tv_nsec -= tmp.tv_nsec;
if (t.tv_nsec < 0)
{
--(t.tv_sec);
t.tv_nsec += 1000000000L;
}
if (what == PNGCP_TIME_READ)
dp->read_time = t, tmp = dp->read_time_total;
else
dp->write_time = t, tmp = dp->write_time_total;
tmp.tv_sec += t.tv_sec;
tmp.tv_nsec += t.tv_nsec;
if (tmp.tv_nsec >= 1000000000L)
{
++(tmp.tv_sec);
tmp.tv_nsec -= 1000000000L;
}
if (what == PNGCP_TIME_READ)
dp->read_time_total = tmp;
else
dp->write_time_total = tmp;
}
}
static void
print_time(const char *what, struct timespec t)
{
printf("%s %.2lu.%.9ld", what, (unsigned long)t.tv_sec, t.tv_nsec);
}
#else /* !PNGCP_TIMING */
#define start_timer(dp, what) ((void)0)
#define end_timer(dp, what) ((void)0)
#endif /* !PNGCP_TIMING */
/* The following is used in main to verify that the final argument is a
* directory:
*/
static int
checkdir(const char *pathname)
{
struct stat buf;
return stat(pathname, &buf) == 0 && S_ISDIR(buf.st_mode);
}
/* Work out whether a path is valid (if not a display_log occurs), a directory
* (1 is returned) or a file *or* non-existent (0 is returned).
*
* Used for a write path.
*/
static int
isdir(struct display *dp, const char *pathname)
{
if (pathname == NULL)
return 0; /* stdout */
else if (pathname[0] == 0)
return 1; /* empty string */
else
{
struct stat buf;
int ret = stat(pathname, &buf);
if (ret == 0) /* the entry exists */
{
if (S_ISDIR(buf.st_mode))
return 1;
/* Else expect an object that exists and can be written: */
if (access(pathname, W_OK) != 0)
display_log(dp, USER_ERROR, "%s: cannot be written (%s)", pathname,
strerror(errno));
return 0; /* file (exists, can be written) */
}
else /* an error */
{
/* Non-existence is fine, other errors are not: */
if (errno != ENOENT)
display_log(dp, USER_ERROR, "%s: invalid output name (%s)",
pathname, strerror(errno));
return 0; /* file (does not exist) */
}
}
}
static void
makename(struct display *dp, const char *dir, const char *infile)
{
/* Make a name for an output file (and check it). */
dp->namebuf[0] = 0;
if (dir == NULL || infile == NULL)
display_log(dp, INTERNAL_ERROR, "NULL name to makename");
else
{
size_t dsize = strlen(dir);
if (dsize <= (sizeof dp->namebuf)-2) /* Allow for name + '/' + '\0' */
{
size_t isize = strlen(infile);
size_t istart = isize-1;
/* This should fail before here: */
if (infile[istart] == '/')
display_log(dp, INTERNAL_ERROR, "infile with trailing /");
memcpy(dp->namebuf, dir, dsize);
if (dsize > 0 && dp->namebuf[dsize-1] != '/')
dp->namebuf[dsize++] = '/';
/* Find the rightmost non-/ character: */
while (istart > 0 && infile[istart-1] != '/')
--istart;
isize -= istart;
infile += istart;
if (dsize+isize < (sizeof dp->namebuf)) /* dsize + infile + '\0' */
{
memcpy(dp->namebuf+dsize, infile, isize+1);
if (isdir(dp, dp->namebuf))
display_log(dp, USER_ERROR, "%s: output file is a directory",
dp->namebuf);
}
else
{
dp->namebuf[dsize] = 0; /* allowed for: -2 at start */
display_log(dp, USER_ERROR, "%s%s: output file name too long",
dp->namebuf, infile);
}
}
else
display_log(dp, USER_ERROR, "%s: output directory name too long", dir);
}
}
/* error handler callbacks for libpng */
static void PNGCBAPI
display_warning(png_structp pp, png_const_charp warning)
{
struct display *dp = get_dp(pp);
/* This is used to prevent repeated warnings while searching */
if (!dp->no_warnings)
display_log(get_dp(pp), LIBPNG_WARNING, "%s", warning);
}
static void PNGCBAPI
display_error(png_structp pp, png_const_charp error)
{
struct display *dp = get_dp(pp);
display_log(dp, LIBPNG_ERROR, "%s", error);
}
static void
display_start_read(struct display *dp, const char *filename)
{
if (filename != NULL)
{
dp->filename = filename;
dp->fp = fopen(filename, "rb");
}
else
{
dp->filename = "<stdin>";
dp->fp = stdin;
}
dp->w = dp->h = 0U;
dp->bpp = 0U;
dp->size = 0U;
dp->read_size = 0U;
if (dp->fp == NULL)
display_log(dp, USER_ERROR, "file open failed (%s)", strerror(errno));
}
static void PNGCBAPI
read_function(png_structp pp, png_bytep data, png_size_t size)
{
struct display *dp = get_dp(pp);
if (size == 0U || fread(data, size, 1U, dp->fp) == 1U)
dp->read_size += size;
else
{
if (feof(dp->fp))
display_log(dp, LIBPNG_ERROR, "PNG file truncated");
else
display_log(dp, LIBPNG_ERROR, "PNG file read failed (%s)",
strerror(errno));
}
}
static void
read_png(struct display *dp, const char *filename)
{
display_clean_read(dp); /* safety */
display_start_read(dp, filename);
dp->read_pp = png_create_read_struct(PNG_LIBPNG_VER_STRING, dp,
display_error, display_warning);
if (dp->read_pp == NULL)
display_log(dp, LIBPNG_ERROR, "failed to create read struct");
# ifdef PNG_BENIGN_ERRORS_SUPPORTED
png_set_benign_errors(dp->read_pp, 1/*allowed*/);
# endif /* BENIGN_ERRORS */
# ifdef FIX_INDEX
if ((dp->options & FIX_INDEX) != 0)
png_set_check_for_invalid_index(dp->read_pp, 1/*on, no warning*/);
# ifdef IGNORE_INDEX
else
# endif /* IGNORE_INDEX */
# endif /* FIX_INDEX */
# ifdef IGNORE_INDEX
if ((dp->options & IGNORE_INDEX) != 0) /* DANGEROUS */
png_set_check_for_invalid_index(dp->read_pp, -1/*off completely*/);
# endif /* IGNORE_INDEX */
/* The png_read_png API requires us to make the info struct, but it does the
* call to png_read_info.
*/
dp->ip = png_create_info_struct(dp->read_pp);
if (dp->ip == NULL)
png_error(dp->read_pp, "failed to create info struct");
/* Set the IO handling */
png_set_read_fn(dp->read_pp, dp, read_function);
# ifdef PNG_HANDLE_AS_UNKNOWN_SUPPORTED
png_set_keep_unknown_chunks(dp->read_pp, PNG_HANDLE_CHUNK_ALWAYS, NULL,
0);
# endif /* HANDLE_AS_UNKNOWN */
# ifdef PNG_SET_USER_LIMITS_SUPPORTED
/* Remove the user limits, if any */
png_set_user_limits(dp->read_pp, 0x7fffffff, 0x7fffffff);
# endif /* SET_USER_LIMITS */
/* Now read the PNG. */
start_timer(dp, PNGCP_TIME_READ);
png_read_png(dp->read_pp, dp->ip, 0U/*transforms*/, NULL/*params*/);
end_timer(dp, PNGCP_TIME_READ);
dp->w = png_get_image_width(dp->read_pp, dp->ip);
dp->h = png_get_image_height(dp->read_pp, dp->ip);
dp->ct = png_get_color_type(dp->read_pp, dp->ip);
dp->bpp = png_get_bit_depth(dp->read_pp, dp->ip) *
png_get_channels(dp->read_pp, dp->ip);
{
/* png_get_rowbytes should never return 0 because the value is set by the
* first call to png_set_IHDR, which should have happened by now, but just
* in case:
*/
png_alloc_size_t rb = png_get_rowbytes(dp->read_pp, dp->ip);
if (rb == 0)
png_error(dp->read_pp, "invalid row byte count from libpng");
/* The size calc can overflow. */
if ((MAX_SIZE-dp->h)/rb < dp->h)
png_error(dp->read_pp, "image too large");
dp->size = rb * dp->h + dp->h/*filter byte*/;
}
#ifdef FIX_INDEX
if (dp->ct == PNG_COLOR_TYPE_PALETTE && (dp->options & FIX_INDEX) != 0)
{
int max = png_get_palette_max(dp->read_pp, dp->ip);
png_colorp palette = NULL;
int num = -1;
if (png_get_PLTE(dp->read_pp, dp->ip, &palette, &num) != PNG_INFO_PLTE
|| max < 0 || num <= 0 || palette == NULL)
display_log(dp, LIBPNG_ERROR, "invalid png_get_PLTE result");
if (max >= num)
{
/* 'Fix' the palette. */
int i;
png_color newpal[256];
for (i=0; i<num; ++i)
newpal[i] = palette[i];
/* Fill in any remainder with a warning color: */
for (; i<=max; ++i)
{
newpal[i].red = 0xbe;
newpal[i].green = 0xad;
newpal[i].blue = 0xed;
}
png_set_PLTE(dp->read_pp, dp->ip, newpal, i);
}
}
#endif /* FIX_INDEX */
display_clean_read(dp);
dp->operation = "none";
}
static void
display_start_write(struct display *dp, const char *filename)
{
assert(dp->fp == NULL);
if ((dp->options & NOWRITE) != 0)
dp->output_file = "<no write>";
else
{
if (filename != NULL)
{
dp->output_file = filename;
dp->fp = fopen(filename, "wb");
}
else
{
dp->output_file = "<stdout>";
dp->fp = stdout;
}
if (dp->fp == NULL)
display_log(dp, USER_ERROR, "%s: file open failed (%s)",
dp->output_file, strerror(errno));
}
}
static void PNGCBAPI
write_function(png_structp pp, png_bytep data, png_size_t size)
{
struct display *dp = get_dp(pp);
/* The write fail is classed as a USER_ERROR, so --quiet does not turn it
* off, this seems more likely to be correct.
*/
if (dp->fp == NULL || fwrite(data, size, 1U, dp->fp) == 1U)
{
dp->write_size += size;
if (dp->write_size < size || dp->write_size == MAX_SIZE)
png_error(pp, "IDAT size overflow");
}
else
display_log(dp, USER_ERROR, "%s: PNG file write failed (%s)",
dp->output_file, strerror(errno));
}
/* Compression option, 'method' is never set: there is no choice.
*
* IMPORTANT: the order of the entries in this macro determines the preference
* order when two different combos of two of these options produce an IDAT of
* the same size. The logic here is to put the things that affect the decoding
* of the PNG image ahead of those that are relevant only to the encoding.
*/
#define SET_COMPRESSION\
SET(strategy, strategy);\
SET(windowBits, window_bits);\
SET(level, level);\
SET(memLevel, mem_level);
#ifdef PNG_WRITE_CUSTOMIZE_COMPRESSION_SUPPORTED
static void
search_compression(struct display *dp)
{
/* Like set_compression below but use a more restricted search than 'all' */
int val;
# define SET(name, func) if (getsearchopts(dp, #name, &val))\
png_set_compression_ ## func(dp->write_pp, val);
SET_COMPRESSION
# undef SET
}
static void
set_compression(struct display *dp)
{
int val;
# define SET(name, func) if (getallopts(dp, #name, &val))\
png_set_compression_ ## func(dp->write_pp, val);
SET_COMPRESSION
# undef SET
}
#ifdef PNG_SW_COMPRESS_level /* 1.7.0+ */
static void
set_ICC_profile_compression(struct display *dp)
{
int val;
# define SET(name, func) if (getallopts(dp, "ICC-profile-" #name, &val))\
png_set_ICC_profile_compression_ ## func(dp->write_pp, val);
SET_COMPRESSION
# undef SET
}
#else
# define set_ICC_profile_compression(dp) ((void)0)
#endif
#else
# define search_compression(dp) ((void)0)
# define set_compression(dp) ((void)0)
# define set_ICC_profile_compression(dp) ((void)0)
#endif /* WRITE_CUSTOMIZE_COMPRESSION */
#ifdef PNG_WRITE_CUSTOMIZE_ZTXT_COMPRESSION_SUPPORTED
static void
set_text_compression(struct display *dp)
{
int val;
# define SET(name, func) if (getallopts(dp, "text-" #name, &val))\
png_set_text_compression_ ## func(dp->write_pp, val);
SET_COMPRESSION
# undef SET
}
#else
# define set_text_compression(dp) ((void)0)
#endif /* WRITE_CUSTOMIZE_ZTXT_COMPRESSION */
static void
write_png(struct display *dp, const char *destname)
{
display_clean_write(dp); /* safety */
display_start_write(dp, destname);
dp->write_pp = png_create_write_struct(PNG_LIBPNG_VER_STRING, dp,
display_error, display_warning);
if (dp->write_pp == NULL)
display_log(dp, LIBPNG_ERROR, "failed to create write png_struct");
# ifdef PNG_BENIGN_ERRORS_SUPPORTED
png_set_benign_errors(dp->write_pp, 1/*allowed*/);
# endif /* BENIGN_ERRORS */
png_set_write_fn(dp->write_pp, dp, write_function, NULL/*flush*/);
#ifdef IGNORE_INDEX
if ((dp->options & IGNORE_INDEX) != 0) /* DANGEROUS */
png_set_check_for_invalid_index(dp->write_pp, -1/*off completely*/);
#endif /* IGNORE_INDEX */
/* Restore the text chunks when using libpng 1.6 or less; this is a macro
* which expands to nothing in 1.7+ In earlier versions it tests
* dp->text_stashed, which is only set (below) *after* the first write.
*/
text_restore(dp);
# ifdef PNG_HANDLE_AS_UNKNOWN_SUPPORTED
png_set_keep_unknown_chunks(dp->write_pp, PNG_HANDLE_CHUNK_ALWAYS, NULL,
0);
# endif /* HANDLE_AS_UNKNOWN */
# ifdef PNG_SET_USER_LIMITS_SUPPORTED
/* Remove the user limits, if any */
png_set_user_limits(dp->write_pp, 0x7fffffff, 0x7fffffff);
# endif
/* OPTION HANDLING */
/* compression outputs, IDAT and zTXt/iTXt: */
dp->tsp = dp->nsp;
dp->nsp = dp->csp = 0;
# ifdef PNG_SW_COMPRESS_png_level
{
int val;
/* This sets everything, but then the following options just override
* the specific settings for ICC profiles and text.
*/
if (getallopts(dp, "compression", &val))
png_set_compression(dp->write_pp, val);
if (getallopts(dp, "ICC-profile-compression", &val))
png_set_ICC_profile_compression(dp->write_pp, val);
if (getallopts(dp, "text-compression", &val))
png_set_text_compression(dp->write_pp, val);
}
# endif /* png_level support */
if (dp->options & SEARCH)
search_compression(dp);
else
set_compression(dp);
set_ICC_profile_compression(dp);
set_text_compression(dp);
{
int val;
/* The permitted range is 1..0x7FFFFFFF, so the cast is safe */
if (get_option(dp, "IDAT-size", &val))
png_set_IDAT_size(dp->write_pp, val);
}
/* filter handling */
# ifdef PNG_WRITE_FILTER_SUPPORTED
{
int val;
if (get_option(dp, "filter", &val))
png_set_filter(dp->write_pp, PNG_FILTER_TYPE_BASE, val);
}
# endif /* WRITE_FILTER */
/* This just uses the 'read' info_struct directly, it contains the image. */
dp->write_size = 0U;
start_timer(dp, PNGCP_TIME_WRITE);
png_write_png(dp->write_pp, dp->ip, 0U/*transforms*/, NULL/*params*/);
end_timer(dp, PNGCP_TIME_WRITE);
/* Make sure the file was written ok: */
if (dp->fp != NULL)
{
FILE *fp = dp->fp;
dp->fp = NULL;
if (fclose(fp))
display_log(dp, APP_ERROR, "%s: write failed (%s)",
destname == NULL ? "stdout" : destname, strerror(errno));
}
/* Clean it on the way out - if control returns to the caller then the
* written_file contains the required data.
*/
display_clean_write(dp);
dp->operation = "none";
}
static void
set_windowBits_hi(struct display *dp)
{
/* windowBits is in the range 8..15 but zlib maps '8' to '9' so it is only
* worth using if the data size is 256 byte or less.
*/
int wb = MAX_WBITS; /* for large images */
int i = VLSIZE(windowBits_IDAT);
while (wb > 8 && dp->size <= 1U<<(wb-1)) --wb;
while (--i >= 0) if (VLNAME(windowBits_IDAT)[i].name == range_hi) break;
assert(i > 1); /* vl_windowBits_IDAT always has a RANGE() */
VLNAME(windowBits_IDAT)[i].value = wb;
assert(VLNAME(windowBits_IDAT)[--i].name == range_lo);
VLNAME(windowBits_IDAT)[i].value = wb > 8 ? 9 : 8;
/* If wb == 8 then any search has been restricted to just one windowBits
* entry. Record that here to avoid producing a spurious app-level warning
* above.
*/
if (wb == 8)
dp->min_windowBits = OPTIND(dp, windowBits);
}
static int
better_options(const struct display *dp)
{
/* Are these options better than the best found so far? Normally the
* options are tested in preference order, best first, however when doing a
* search operation on a range the range values are tested out of order. In
* that case preferable options will get tested later.
*
* This function looks through the stack from the bottom up looking for an
* option that does not match the current best value. When it finds one it
* checks to see if it is more or less desireable and returns true or false
* as appropriate.
*
* Notice that this means that the order options are pushed onto the stack
* conveys a priority; lower/earlier options are more important than later
* ones.
*/
unsigned int sp;
for (sp=0; sp<dp->csp; ++sp)
{
int c = compare_option(dp, sp);
if (c < 0)
return 0; /* worse */
else if (c > 0)
return 1; /* better */
}
assert(0 && "unreached");
}
static void
print_search_results(struct display *dp)
{
assert(dp->filename != NULL);
printf("%s [%ld x %ld %d bpp %s, %lu bytes] %lu -> %lu with '%s'\n",
dp->filename, (unsigned long)dp->w, (unsigned long)dp->h, dp->bpp,
cts(dp->ct), (unsigned long)dp->size, (unsigned long)dp->read_size,
(unsigned long)dp->best_size, dp->best);
fflush(stdout);
}
static void
log_search(struct display *dp, unsigned int log_depth)
{
/* Log, and reset, the search so far: */
if (dp->nsp/*next entry to change*/ <= log_depth)
{
print_search_results(dp);
/* Start again with this entry: */
dp->best_size = MAX_SIZE;
}
}
static void
cp_one_file(struct display *dp, const char *filename, const char *destname)
{
unsigned int log_depth;
dp->filename = filename;
dp->operation = "read";
dp->no_warnings = 0;
/* Read it then write it: */
if (filename != NULL && access(filename, R_OK) != 0)
display_log(dp, USER_ERROR, "%s: invalid file name (%s)",
filename, strerror(errno));
read_png(dp, filename);
/* But 'destname' may be a directory. */
dp->operation = "write";
/* Limit the upper end of the windowBits range for this file */
set_windowBits_hi(dp);
/* For logging, depth to log: */
{
int val;
if (get_option(dp, "log-depth", &val) && val >= 0)
log_depth = (unsigned int)/*SAFE*/val;
else
log_depth = 0U;
}
if (destname != NULL) /* else stdout */
{
if (isdir(dp, destname))
{
makename(dp, destname, filename);
destname = dp->namebuf;
}
else if (access(destname, W_OK) != 0 && errno != ENOENT)
display_log(dp, USER_ERROR, "%s: invalid output name (%s)", destname,
strerror(errno));
}
dp->nsp = 0;
dp->curr[0] = 0; /* acts as a flag for the caller */
dp->opt_string_start = 0;
dp->best[0] = 0; /* safety */
dp->best_size = MAX_SIZE;
write_png(dp, destname);
/* Initialize the 'best' fields: */
strcpy(dp->best, dp->curr);
dp->best_size = dp->write_size;
if (dp->nsp > 0) /* interating over lists */
{
char *tmpname, tmpbuf[(sizeof dp->namebuf) + 4];
assert(dp->curr[0] == ' ' && dp->tsp > 0);
/* Cancel warnings on subsequent writes */
log_search(dp, log_depth);
dp->no_warnings = 1;
/* Make a temporary name for the subsequent tests: */
if (destname != NULL)
{
strcpy(tmpbuf, destname);
strcat(tmpbuf, ".tmp"); /* space for .tmp allocated above */
tmpname = tmpbuf;
}
else
tmpname = NULL; /* stdout */
/* Loop to find the best option. */
do
{
write_png(dp, tmpname);
/* And compare the sizes (the write function makes sure write_size
* doesn't overflow.)
*/
assert(dp->csp > 0);
if (dp->write_size < dp->best_size ||
(dp->write_size == dp->best_size && better_options(dp)))
{
if (destname != NULL && rename(tmpname, destname) != 0)
display_log(dp, APP_ERROR, "rename %s %s failed (%s)", tmpname,
destname, strerror(errno));
strcpy(dp->best, dp->curr);
dp->best_size = dp->write_size;
}
else if (tmpname != NULL && unlink(tmpname) != 0)
display_log(dp, APP_WARNING, "unlink %s failed (%s)", tmpname,
strerror(errno));
log_search(dp, log_depth);
}
while (dp->nsp > 0);
/* Do this for the 'sizes' option so that it reports the correct size. */
dp->write_size = dp->best_size;
}
}
static int
cppng(struct display *dp, const char *file, const char *gv dest)
/* Exists solely to isolate the setjmp clobbers which some versions of GCC
* erroneously generate.
*/
{
int ret = setjmp(dp->error_return);
if (ret == 0)
{
dp->errset = 1;
cp_one_file(dp, file, dest);
dp->errset = 0;
return 0;
}
else
{
dp->errset = 0;
if (ret < ERRORS) /* shouldn't longjmp on warnings */
display_log(dp, INTERNAL_ERROR, "unexpected return code %d", ret);
return ret;
}
}
int
main(const int argc, const char * const * const argv)
{
/* For each file on the command line test it with a range of transforms */
int option_end;
struct display d;
display_init(&d);
d.operation = "options";
for (option_end = 1;
option_end < argc && opt_check(&d, argv[option_end]);
++option_end)
{
}
/* Do a quick check on the directory target case; when there are more than
* two arguments the last one must be a directory.
*/
if (!(d.options & NOWRITE) && option_end+2 < argc && !checkdir(argv[argc-1]))
{
fprintf(stderr,
"pngcp: %s: directory required with more than two arguments\n",
argv[argc-1]);
return 99;
}
{
int errors = 0;
int i = option_end;
/* Do this at least once; if there are no arguments stdin/stdout are used.
*/
d.operation = "files";
do
{
const char *infile = NULL;
const char *outfile = NULL;
int ret;
if (i < argc)
{
infile = argv[i++];
if (!(d.options & NOWRITE) && i < argc)
outfile = argv[argc-1];
}
ret = cppng(&d, infile, outfile);
if (ret)
{
if (ret > QUIET) /* abort on user or internal error */
return 99;
/* An error: the output is meaningless */
}
else if (d.best[0] != 0)
{
/* This result may already have been output, in which case best_size
* has been reset.
*/
if (d.best_size < MAX_SIZE)
print_search_results(&d);
}
else if (d.options & SIZES)
{
printf("%s [%ld x %ld %d bpp %s, %lu bytes] %lu -> %lu [0x%lx]\n",
infile, (unsigned long)d.w, (unsigned long)d.h, d.bpp,
cts(d.ct), (unsigned long)d.size, (unsigned long)d.read_size,
(unsigned long)d.write_size, (unsigned long)d.results);
fflush(stdout);
}
/* Here on any return, including failures, except user/internal issues
*/
{
const int pass = (d.options & STRICT) ?
RESULT_STRICT(d.results) : RESULT_RELAXED(d.results);
if (!pass)
++errors;
if (d.options & LOG)
{
int j;
printf("%s: pngcp", pass ? "PASS" : "FAIL");
for (j=1; j<option_end; ++j)
printf(" %s", argv[j]);
if (infile != NULL)
printf(" %s", infile);
# ifdef PNG_PNGCP_TIMING_SUPPORTED
/* When logging output the files for each file, if enabled. */
if ((d.value[OPTIND(&d,time)] & PNGCP_TIME_READ) != 0)
print_time(" read", d.read_time);
if ((d.value[OPTIND(&d,time)] & PNGCP_TIME_WRITE) != 0)
print_time(" write", d.write_time);
# endif /* PNGCP_TIMING */
printf("\n");
fflush(stdout);
}
}
display_clean(&d);
}
while (i+!(d.options & NOWRITE) < argc);
/* I.e. for write cases after the first time through the loop require
* there to be at least two arguments left and for the last one to be a
* directory (this was checked above).
*/
/* Release allocated memory */
display_destroy(&d);
# ifdef PNG_PNGCP_TIMING_SUPPORTED
{
int output = 0;
if ((d.value[OPTIND(&d,time)] & PNGCP_TIME_READ) != 0)
print_time("read", d.read_time_total), output = 1;
if ((d.value[OPTIND(&d,time)] & PNGCP_TIME_WRITE) != 0)
{
if (output) putchar(' ');
print_time("write", d.write_time_total);
output = 1;
}
if (output) putchar('\n');
}
# endif /* PNGCP_TIMING */
return errors != 0;
}
}
#else /* !READ_PNG || !WRITE_PNG */
int
main(void)
{
fprintf(stderr, "pngcp: no support for png_read/write_image\n");
return 77;
}
#endif /* !READ_PNG || !WRITE_PNG */