/*
* This file is part of ltrace.
* Copyright (C) 2012, 2013, 2014 Petr Machata, Red Hat Inc.
* Copyright (C) 2009,2010 Joe Damato
* Copyright (C) 1998,1999,2002,2003,2004,2007,2008,2009 Juan Cespedes
* Copyright (C) 2006 Ian Wienand
* Copyright (C) 2006 Steve Fink
* Copyright (C) 2006 Paul Gilliam, IBM Corporation
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License as
* published by the Free Software Foundation; either version 2 of the
* License, or (at your option) any later version.
*
* This program is distributed in the hope that it will be useful, but
* WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
* 02110-1301 USA
*/
#include "config.h"
#include <sys/ioctl.h>
#include <sys/stat.h>
#include <sys/types.h>
#include <assert.h>
#include <errno.h>
#include <fcntl.h>
#include <getopt.h>
#include <limits.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include "common.h"
#include "filter.h"
#include "glob.h"
#include "demangle.h"
struct options_t options = {
.align = DEFAULT_ALIGN, /* alignment column for results */
.user = NULL, /* username to run command as */
.syscalls = 0, /* display syscalls */
#ifdef USE_DEMANGLE
.demangle = 0, /* Demangle low-level symbol names */
#endif
.indent = 0, /* indent output according to program flow */
.output = NULL, /* output to a specific file */
.summary = 0, /* Report a summary on program exit */
.debug = 0, /* debug */
.arraylen = DEFAULT_ARRAYLEN, /* maximum # array elements to print */
.strlen = DEFAULT_STRLEN, /* maximum # of bytes printed in strings */
.follow = 0, /* trace child processes */
};
static char *progname; /* Program name (`ltrace') */
int opt_i = 0; /* instruction pointer */
int opt_r = 0; /* print relative timestamp */
int opt_t = 0; /* print absolute timestamp */
int opt_T = 0; /* show the time spent inside each call */
/* List of pids given to option -p: */
struct opt_p_t *opt_p = NULL; /* attach to process with a given pid */
/* Vector of struct opt_F_t. */
struct vect opt_F;
static void
err_usage(void) {
fprintf(stderr, "Try `%s --help' for more information.\n", progname);
exit(1);
}
static void
usage(void) {
fprintf(stdout, "Usage: %s [option ...] [command [arg ...]]\n"
"Trace library calls of a given program.\n\n"
" -a, --align=COLUMN align return values in a secific column.\n"
" -A MAXELTS maximum number of array elements to print.\n"
" -b, --no-signals don't print signals.\n"
" -c count time and calls, and report a summary on exit.\n"
# ifdef USE_DEMANGLE
" -C, --demangle decode low-level symbol names into user-level names.\n"
# endif
" -D, --debug=MASK enable debugging (see -Dh or --debug=help).\n"
" -Dh, --debug=help show help on debugging.\n"
" -e FILTER modify which library calls to trace.\n"
" -f trace children (fork() and clone()).\n"
" -F, --config=FILE load alternate configuration file (may be repeated).\n"
" -h, --help display this help and exit.\n"
" -i print instruction pointer at time of library call.\n"
" -l, --library=LIBRARY_PATTERN only trace symbols implemented by this library.\n"
" -L do NOT display library calls.\n"
" -n, --indent=NR indent output by NR spaces for each call level nesting.\n"
" -o, --output=FILENAME write the trace output to file with given name.\n"
" -p PID attach to the process with the process ID pid.\n"
" -r print relative timestamps.\n"
" -s STRSIZE specify the maximum string size to print.\n"
" -S trace system calls as well as library calls.\n"
" -t, -tt, -ttt print absolute timestamps.\n"
" -T show the time spent inside each call.\n"
" -u USERNAME run command with the userid, groupid of username.\n"
" -V, --version output version information and exit.\n"
#if defined(HAVE_UNWINDER)
" -w, --where=NR print backtrace showing NR stack frames at most.\n"
#endif /* defined(HAVE_UNWINDER) */
" -x FILTER modify which static functions to trace.\n"
"\nReport bugs to ltrace-devel@lists.alioth.debian.org\n",
progname);
}
static void
usage_debug(void) {
fprintf(stdout, "%s debugging option, --debug=<octal> or -D<octal>:\n", progname);
fprintf(stdout,
"\n"
" number ref. in source description\n"
" 1 general Generally helpful progress information\n"
" 10 event Shows every event received by a traced process\n"
" 20 process Shows actions carried upon a traced processes\n"
" 40 function Shows every entry to internal functions\n"
"\n"
"Debugging options are mixed using bitwise-or.\n"
"Note that the meanings and values are subject to change.\n"
"Also note that these values are used inconsistently in ltrace, and the\n"
"only debuglevel that you can rely on is -D77 that will show everything.\n"
);
}
static char *
search_for_command(char *filename) {
static char pathname[PATH_MAX];
char *path;
int m, n;
if (strchr(filename, '/')) {
return filename;
}
for (path = getenv("PATH"); path && *path; path += m) {
if (strchr(path, ':')) {
n = strchr(path, ':') - path;
m = n + 1;
} else {
m = n = strlen(path);
}
if (n + strlen(filename) + 1 >= PATH_MAX) {
fprintf(stderr, "Error: filename too long.\n");
exit(1);
}
strncpy(pathname, path, n);
if (n && pathname[n - 1] != '/') {
pathname[n++] = '/';
}
strcpy(pathname + n, filename);
if (!access(pathname, X_OK)) {
return pathname;
}
}
return filename;
}
static void
guess_cols(void) {
struct winsize ws;
char *c;
options.align = DEFAULT_ALIGN;
c = getenv("COLUMNS");
if (c && *c) {
char *endptr;
int cols;
cols = strtol(c, &endptr, 0);
if (cols > 0 && !*endptr) {
options.align = cols * 5 / 8;
}
} else if (ioctl(1, TIOCGWINSZ, &ws) != -1 && ws.ws_col > 0) {
options.align = ws.ws_col * 5 / 8;
} else if (ioctl(2, TIOCGWINSZ, &ws) != -1 && ws.ws_col > 0) {
options.align = ws.ws_col * 5 / 8;
}
}
static int
compile_libname(const char *expr, const char *a_lib, int lib_re_p,
struct filter_lib_matcher *matcher)
{
if (strcmp(a_lib, "MAIN") == 0) {
filter_lib_matcher_main_init(matcher);
} else {
/* Add ^ and $ to the library expression as well. */
char lib[strlen(a_lib) + 3];
sprintf(lib, "^%s$", a_lib);
enum filter_lib_matcher_type type
= lib[0] == '/' ? FLM_PATHNAME : FLM_SONAME;
regex_t lib_re;
int status = (lib_re_p ? regcomp : globcomp)(&lib_re, lib, 0);
if (status != 0) {
char buf[100];
regerror(status, &lib_re, buf, sizeof buf);
fprintf(stderr, "Couldn't compile '%s': %s.\n",
expr, buf);
return -1;
}
filter_lib_matcher_name_init(matcher, type, lib_re);
}
return 0;
}
static int
add_filter_rule(struct filter *filt, const char *expr,
enum filter_rule_type type,
const char *a_sym, int sym_re_p,
const char *a_lib, int lib_re_p)
{
struct filter_rule *rule = malloc(sizeof(*rule));
struct filter_lib_matcher *matcher = malloc(sizeof(*matcher));
if (rule == NULL || matcher == NULL) {
fail:
free(rule);
free(matcher);
return -1;
}
regex_t symbol_re;
{
/* Add ^ to the start of expression and $ to the end, so that
* we match the whole symbol name. Let the user write the "*"
* explicitly if they wish. */
char sym[strlen(a_sym) + 3];
sprintf(sym, "^%s$", a_sym);
int status = (sym_re_p ? regcomp : globcomp)
(&symbol_re, sym, 0);
if (status != 0) {
char buf[100];
regerror(status, &symbol_re, buf, sizeof buf);
fprintf(stderr, "Couldn't compile '%s': %s.\n",
expr, buf);
goto fail;
}
}
if (compile_libname(expr, a_lib, lib_re_p, matcher) < 0) {
regfree(&symbol_re);
goto fail;
}
filter_rule_init(rule, type, matcher, symbol_re);
filter_add_rule(filt, rule);
return 0;
}
static int
grok_libname_pattern(char **libnamep, char **libendp)
{
char *libname = *libnamep;
char *libend = *libendp;
if (libend[0] != '/')
return 0;
*libend-- = 0;
if (libname != libend && libname[0] == '/')
++libname;
else
fprintf(stderr, "Unmatched '/' in library name.\n");
*libendp = libend;
*libnamep = libname;
return 1;
}
static int
parse_filter(struct filter *filt, char *expr, int operators)
{
/* Filter is a chain of sym@lib rules separated by '-' or '+'.
* If the filter expression starts with '-', the missing
* initial rule is implicitly *@*. */
enum filter_rule_type type = FR_ADD;
while (*expr != 0) {
size_t s = strcspn(expr, &"-+@"[operators ? 0 : 2]);
char *symname = expr;
char *libname;
char *next = expr + s + 1;
enum filter_rule_type this_type = type;
if (expr[s] == 0) {
libname = "*";
expr = next - 1;
} else if (expr[s] == '-' || expr[s] == '+') {
type = expr[s] == '-' ? FR_SUBTRACT : FR_ADD;
expr[s] = 0;
libname = "*";
expr = next;
} else {
assert(expr[s] == '@');
expr[s] = 0;
s = strcspn(next, &"-+"[operators ? 0 : 2]);
if (s == 0) {
libname = "*";
expr = next;
} else if (next[s] == 0) {
expr = next + s;
libname = next;
} else {
assert(next[s] == '-' || next[s] == '+');
type = next[s] == '-' ? FR_SUBTRACT : FR_ADD;
next[s] = 0;
expr = next + s + 1;
libname = next;
}
}
assert(*libname != 0);
char *symend = symname + strlen(symname) - 1;
char *libend = libname + strlen(libname) - 1;
int sym_is_re = 0;
int lib_is_re = 0;
/*
* /xxx/@... and ...@/xxx/ means that xxx are regular
* expressions. They are globs otherwise.
*
* /xxx@yyy/ is the same as /xxx/@/yyy/
*
* @/xxx matches library path name
* @.xxx matches library relative path name
*/
if (symname[0] == '/') {
if (symname != symend && symend[0] == '/') {
++symname;
*symend-- = 0;
sym_is_re = 1;
} else {
sym_is_re = 1;
lib_is_re = 1;
++symname;
/* /XXX@YYY/ is the same as
* /XXX/@/YYY/. */
if (libend[0] != '/')
fprintf(stderr, "Unmatched '/'"
" in symbol name.\n");
else
*libend-- = 0;
}
}
/* If libname ends in '/', then we expect '/' in the
* beginning too. Otherwise the initial '/' is part
* of absolute file name. */
if (!lib_is_re)
lib_is_re = grok_libname_pattern(&libname, &libend);
if (*symname == 0) /* /@AA/ */
symname = "*";
if (*libname == 0) /* /aa@/ */
libname = "*";
add_filter_rule(filt, expr, this_type,
symname, sym_is_re,
libname, lib_is_re);
}
return 0;
}
static struct filter *
recursive_parse_chain(const char *orig, char *expr, int operators)
{
struct filter *filt = malloc(sizeof(*filt));
if (filt == NULL) {
fprintf(stderr, "(Part of) filter will be ignored: '%s': %s.\n",
expr, strerror(errno));
return NULL;
}
filter_init(filt);
if (parse_filter(filt, expr, operators) < 0) {
fprintf(stderr, "Filter '%s' will be ignored.\n", orig);
free(filt);
filt = NULL;
}
return filt;
}
static struct filter **
slist_chase_end(struct filter **begin)
{
for (; *begin != NULL; begin = &(*begin)->next)
;
return begin;
}
static void
parse_filter_chain(const char *expr, struct filter **retp)
{
char *str = strdup(expr);
if (str == NULL) {
fprintf(stderr, "Filter '%s' will be ignored: %s.\n",
expr, strerror(errno));
return;
}
/* Support initial '!' for backward compatibility. */
if (str[0] == '!')
str[0] = '-';
*slist_chase_end(retp) = recursive_parse_chain(expr, str, 1);
free(str);
}
static int
parse_int(const char *optarg, char opt, int min, int max)
{
char *endptr;
long int l = strtol(optarg, &endptr, 0);
if (l < min || (max != 0 && l > max)
|| *optarg == 0 || *endptr != 0) {
const char *fmt = max != 0
? "Invalid argument to -%c: '%s'. Use integer %d..%d.\n"
: "Invalid argument to -%c: '%s'. Use integer >=%d.\n";
fprintf(stderr, fmt, opt, optarg, min, max);
exit(1);
}
return (int)l;
}
int
parse_colon_separated_list(const char *paths, struct vect *vec)
{
/* PATHS contains a colon-separated list of directories and
* files to load. It's modeled after shell PATH variable,
* which doesn't allow escapes. PYTHONPATH in CPython behaves
* the same way. So let's follow suit, it makes things easier
* to us. */
char *clone = strdup(paths);
if (clone == NULL) {
fprintf(stderr, "Couldn't parse argument %s: %s.\n",
paths, strerror(errno));
return -1;
}
/* It's undesirable to use strtok, because we want the string
* "a::b" to have three elements. */
char *tok = clone - 1;
char *end = clone + strlen(clone);
while (tok < end) {
++tok;
size_t len = strcspn(tok, ":");
tok[len] = 0;
struct opt_F_t arg = {
.pathname = tok,
.own_pathname = tok == clone,
};
if (VECT_PUSHBACK(vec, &arg) < 0)
/* Presumably this is not a deal-breaker. */
fprintf(stderr, "Couldn't store component of %s: %s.\n",
paths, strerror(errno));
tok += len;
}
return 0;
}
void
opt_F_destroy(struct opt_F_t *entry)
{
if (entry == NULL)
return;
if (entry->own_pathname)
free(entry->pathname);
}
enum opt_F_kind
opt_F_get_kind(struct opt_F_t *entry)
{
if (entry->kind == OPT_F_UNKNOWN) {
struct stat st;
if (lstat(entry->pathname, &st) < 0) {
fprintf(stderr, "Couldn't stat %s: %s\n",
entry->pathname, strerror(errno));
entry->kind = OPT_F_BROKEN;
} else if (S_ISDIR(st.st_mode)) {
entry->kind = OPT_F_DIR;
} else if (S_ISREG(st.st_mode) || S_ISLNK(st.st_mode)) {
entry->kind = OPT_F_FILE;
} else {
fprintf(stderr, "%s is neither a regular file, "
"nor a directory.\n", entry->pathname);
entry->kind = OPT_F_BROKEN;
}
}
assert(entry->kind != OPT_F_UNKNOWN);
return entry->kind;
}
char **
process_options(int argc, char **argv)
{
VECT_INIT(&opt_F, struct opt_F_t);
progname = argv[0];
options.output = stderr;
options.no_signals = 0;
#if defined(HAVE_UNWINDER)
options.bt_depth = -1;
#endif /* defined(HAVE_UNWINDER) */
guess_cols();
int libcalls = 1;
while (1) {
int c;
char *p;
#ifdef HAVE_GETOPT_LONG
int option_index = 0;
static struct option long_options[] = {
{"align", 1, 0, 'a'},
{"config", 1, 0, 'F'},
{"debug", 1, 0, 'D'},
# ifdef USE_DEMANGLE
{"demangle", 0, 0, 'C'},
# endif
{"indent", 1, 0, 'n'},
{"help", 0, 0, 'h'},
{"library", 1, 0, 'l'},
{"output", 1, 0, 'o'},
{"version", 0, 0, 'V'},
{"no-signals", 0, 0, 'b'},
# if defined(HAVE_UNWINDER)
{"where", 1, 0, 'w'},
# endif /* defined(HAVE_UNWINDER) */
{0, 0, 0, 0}
};
#endif
const char *opts = "+"
#ifdef USE_DEMANGLE
"C"
#endif
#if defined(HAVE_UNWINDER)
"w:"
#endif
"cfhiLrStTVba:A:D:e:F:l:n:o:p:s:u:x:";
#ifdef HAVE_GETOPT_LONG
c = getopt_long(argc, argv, opts, long_options, &option_index);
#else
c = getopt(argc, argv, opts);
#endif
if (c == -1) {
break;
}
switch (c) {
case 'a':
options.align = parse_int(optarg, 'a', 0, 0);
break;
case 'A':
options.arraylen = parse_int(optarg, 'A', 0, 0);
break;
case 'b':
options.no_signals = 1;
break;
case 'c':
options.summary++;
break;
#ifdef USE_DEMANGLE
case 'C':
options.demangle++;
break;
#endif
case 'D':
if (optarg[0]=='h') {
usage_debug();
exit(0);
}
options.debug = strtoul(optarg,&p,8);
if (*p) {
fprintf(stderr, "%s: --debug requires an octal argument\n", progname);
err_usage();
}
break;
case 'e':
parse_filter_chain(optarg, &options.plt_filter);
break;
case 'f':
options.follow = 1;
break;
case 'F':
parse_colon_separated_list(optarg, &opt_F);
break;
case 'h':
usage();
exit(0);
case 'i':
opt_i++;
break;
case 'l': {
size_t patlen = strlen(optarg);
char buf[patlen + 2];
sprintf(buf, "@%s", optarg);
*slist_chase_end(&options.export_filter)
= recursive_parse_chain(buf, buf, 0);
break;
}
case 'L':
libcalls = 0;
break;
case 'n':
options.indent = parse_int(optarg, 'n', 0, 20);
break;
case 'o':
options.output = fopen(optarg, "w");
if (!options.output) {
fprintf(stderr,
"can't open %s for writing: %s\n",
optarg, strerror(errno));
exit(1);
}
setvbuf(options.output, (char *)NULL, _IOLBF, 0);
fcntl(fileno(options.output), F_SETFD, FD_CLOEXEC);
break;
case 'p':
{
struct opt_p_t *tmp = malloc(sizeof(struct opt_p_t));
if (!tmp) {
perror("ltrace: malloc");
exit(1);
}
tmp->pid = parse_int(optarg, 'p', 1, 0);
tmp->next = opt_p;
opt_p = tmp;
break;
}
case 'r':
opt_r++;
break;
case 's':
options.strlen = parse_int(optarg, 's', 0, 0);
break;
case 'S':
options.syscalls = 1;
break;
case 't':
opt_t++;
break;
case 'T':
opt_T++;
break;
case 'u':
options.user = optarg;
break;
case 'V':
printf("ltrace " PACKAGE_VERSION "\n"
"Copyright (C) 2010-2013 Petr Machata, Red Hat Inc.\n"
"Copyright (C) 1997-2009 Juan Cespedes <cespedes@debian.org>.\n"
"License GPLv2+: GNU GPL version 2 or later <http://gnu.org/licenses/gpl.html>\n"
"This is free software: you are free to change and redistribute it.\n"
"There is NO WARRANTY, to the extent permitted by law.\n");
exit(0);
break;
#if defined(HAVE_UNWINDER)
case 'w':
options.bt_depth = parse_int(optarg, 'w', 1, 0);
break;
#endif /* defined(HAVE_UNWINDER) */
case 'x':
parse_filter_chain(optarg, &options.static_filter);
break;
default:
err_usage();
}
}
argc -= optind;
argv += optind;
/* If neither -e, nor -l, nor -L are used, set default -e.
* Use @MAIN for now, as that's what ltrace used to have in
* the past. XXX Maybe we should make this "*" instead. */
if (libcalls
&& options.plt_filter == NULL
&& options.export_filter == NULL) {
parse_filter_chain("@MAIN", &options.plt_filter);
options.hide_caller = 1;
}
if (!libcalls && options.plt_filter != NULL) {
fprintf(stderr,
"%s: Option -L can't be used with -e or -l.\n",
progname);
err_usage();
}
if (!opt_p && argc < 1) {
fprintf(stderr, "%s: too few arguments\n", progname);
err_usage();
}
if (opt_r && opt_t) {
fprintf(stderr,
"%s: Options -r and -t can't be used together\n",
progname);
err_usage();
}
if (argc > 0) {
command = search_for_command(argv[0]);
}
return &argv[0];
}