/*--------------------------------------------------------------------*/
/*--- Launching valgrind m_launcher.c ---*/
/*--------------------------------------------------------------------*/
/*
This file is part of Valgrind, a dynamic binary instrumentation
framework.
Copyright (C) 2000-2011 Julian Seward
jseward@acm.org
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., 59 Temple Place, Suite 330, Boston, MA
02111-1307, USA.
The GNU General Public License is contained in the file COPYING.
*/
/* Note: this is a "normal" program and not part of Valgrind proper,
and so it doesn't have to conform to Valgrind's arcane rules on
no-glibc-usage etc. */
/* Include valgrind headers before system headers to avoid problems
with the system headers #defining things which are used as names
of structure members in vki headers. */
#include "pub_core_debuglog.h"
#include "pub_core_vki.h" // Avoids warnings from
// pub_core_libcfile.h
#include "pub_core_libcproc.h" // For VALGRIND_LIB, VALGRIND_LAUNCHER
#include "pub_core_ume.h"
#include <assert.h>
#include <ctype.h>
#include <elf.h>
#include <errno.h>
#include <fcntl.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#define PATH_MAX 4096 /* POSIX refers to this a lot but I dunno
where it is defined */
#ifndef EM_X86_64
#define EM_X86_64 62 // elf.h doesn't define this on some older systems
#endif
#ifndef EM_PPC64
#define EM_PPC64 21 // elf.h doesn't define this on Android
#endif
/* Report fatal errors */
__attribute__((noreturn))
static void barf ( const char *format, ... )
{
va_list vargs;
va_start(vargs, format);
fprintf(stderr, "valgrind: Cannot continue: ");
vfprintf(stderr, format, vargs);
fprintf(stderr, "\n");
va_end(vargs);
exit(1);
/*NOTREACHED*/
assert(0);
}
/* Search the path for the client program */
static const char *find_client(const char *clientname)
{
static char fullname[PATH_MAX];
const char *path = getenv("PATH");
const char *colon;
while (path)
{
if ((colon = strchr(path, ':')) == NULL)
{
strcpy(fullname, path);
path = NULL;
}
else
{
memcpy(fullname, path, colon - path);
fullname[colon - path] = '\0';
path = colon + 1;
}
strcat(fullname, "/");
strcat(fullname, clientname);
if (access(fullname, R_OK|X_OK) == 0)
return fullname;
}
return clientname;
}
/* Examine the client and work out which platform it is for */
static const char *select_platform(const char *clientname)
{
int fd;
uint8_t header[4096];
ssize_t n_bytes;
const char *platform = NULL;
VG_(debugLog)(2, "launcher", "selecting platform for '%s'\n", clientname);
if (strchr(clientname, '/') == NULL)
clientname = find_client(clientname);
VG_(debugLog)(2, "launcher", "selecting platform for '%s'\n", clientname);
if ((fd = open(clientname, O_RDONLY)) < 0)
return NULL;
// barf("open(%s): %s", clientname, strerror(errno));
VG_(debugLog)(2, "launcher", "opened '%s'\n", clientname);
n_bytes = read(fd, header, sizeof(header));
close(fd);
if (n_bytes < 2) {
return NULL;
}
VG_(debugLog)(2, "launcher", "read %ld bytes from '%s'\n",
(long int)n_bytes, clientname);
if (header[0] == '#' && header[1] == '!') {
int i = 2;
char *interp = (char *)header + 2;
// Skip whitespace.
while (1) {
if (i == n_bytes) return NULL;
if (' ' != header[i] && '\t' != header[i]) break;
i++;
}
// Get the interpreter name.
interp = &header[i];
while (1) {
if (i == n_bytes) break;
if (isspace(header[i])) break;
i++;
}
if (i == n_bytes) return NULL;
header[i] = '\0';
platform = select_platform(interp);
} else if (n_bytes >= SELFMAG && memcmp(header, ELFMAG, SELFMAG) == 0) {
if (n_bytes >= sizeof(Elf32_Ehdr) && header[EI_CLASS] == ELFCLASS32) {
const Elf32_Ehdr *ehdr = (Elf32_Ehdr *)header;
if (header[EI_DATA] == ELFDATA2LSB) {
if (ehdr->e_machine == EM_386 &&
(ehdr->e_ident[EI_OSABI] == ELFOSABI_SYSV ||
ehdr->e_ident[EI_OSABI] == ELFOSABI_LINUX)) {
platform = "x86-linux";
}
else
if (ehdr->e_machine == EM_ARM &&
(ehdr->e_ident[EI_OSABI] == ELFOSABI_SYSV ||
ehdr->e_ident[EI_OSABI] == ELFOSABI_LINUX)) {
platform = "arm-linux";
}
}
else if (header[EI_DATA] == ELFDATA2MSB) {
if (ehdr->e_machine == EM_PPC &&
(ehdr->e_ident[EI_OSABI] == ELFOSABI_SYSV ||
ehdr->e_ident[EI_OSABI] == ELFOSABI_LINUX)) {
platform = "ppc32-linux";
}
}
} else if (n_bytes >= sizeof(Elf64_Ehdr) && header[EI_CLASS] == ELFCLASS64) {
const Elf64_Ehdr *ehdr = (Elf64_Ehdr *)header;
if (header[EI_DATA] == ELFDATA2LSB) {
if (ehdr->e_machine == EM_X86_64 &&
(ehdr->e_ident[EI_OSABI] == ELFOSABI_SYSV ||
ehdr->e_ident[EI_OSABI] == ELFOSABI_LINUX)) {
platform = "amd64-linux";
}
} else if (header[EI_DATA] == ELFDATA2MSB) {
# if !defined(VGPV_arm_linux_android) && !defined(VGPV_x86_linux_android)
if (ehdr->e_machine == EM_PPC64 &&
(ehdr->e_ident[EI_OSABI] == ELFOSABI_SYSV ||
ehdr->e_ident[EI_OSABI] == ELFOSABI_LINUX)) {
platform = "ppc64-linux";
}
else
if (ehdr->e_machine == EM_S390 &&
(ehdr->e_ident[EI_OSABI] == ELFOSABI_SYSV ||
ehdr->e_ident[EI_OSABI] == ELFOSABI_LINUX)) {
platform = "s390x-linux";
}
# endif
}
}
}
VG_(debugLog)(2, "launcher", "selected platform '%s'\n",
platform ? platform : "unknown");
return platform;
}
/* Where we expect to find all our aux files */
static const char *valgrind_lib = VG_LIBDIR;
int main(int argc, char** argv, char** envp)
{
int i, j, loglevel, r;
const char *toolname = NULL;
const char *clientname = NULL;
const char *platform;
const char *default_platform;
const char *cp;
char *toolfile;
char launcher_name[PATH_MAX+1];
char* new_line;
char** new_env;
/* Start the debugging-log system ASAP. First find out how many
"-d"s were specified. This is a pre-scan of the command line.
At the same time, look for the tool name. */
loglevel = 0;
for (i = 1; i < argc; i++) {
if (argv[i][0] != '-') {
clientname = argv[i];
break;
}
if (0 == strcmp(argv[i], "--")) {
if (i+1 < argc)
clientname = argv[i+1];
break;
}
if (0 == strcmp(argv[i], "-d"))
loglevel++;
if (0 == strncmp(argv[i], "--tool=", 7))
toolname = argv[i] + 7;
}
/* ... and start the debug logger. Now we can safely emit logging
messages all through startup. */
VG_(debugLog_startup)(loglevel, "Stage 1");
/* Make sure we know which tool we're using */
if (toolname) {
VG_(debugLog)(1, "launcher", "tool '%s' requested\n", toolname);
} else {
VG_(debugLog)(1, "launcher",
"no tool requested, defaulting to 'memcheck'\n");
toolname = "memcheck";
}
/* Select a platform to use if we can't decide that by looking at
the executable (eg because it's a shell script). Note that the
default_platform is not necessarily either the primary or
secondary build target. Instead it's chosen to maximise the
chances that /bin/sh will work on it. Hence for a primary
target of ppc64-linux we still choose ppc32-linux as the default
target, because on most ppc64-linux setups, the basic /bin,
/usr/bin, etc, stuff is built in 32-bit mode, not 64-bit
mode. */
if ((0==strcmp(VG_PLATFORM,"x86-linux")) ||
(0==strcmp(VG_PLATFORM,"amd64-linux")) ||
(0==strcmp(VG_PLATFORM,"ppc32-linux")) ||
(0==strcmp(VG_PLATFORM,"ppc64-linux")) ||
(0==strcmp(VG_PLATFORM,"arm-linux")) ||
(0==strcmp(VG_PLATFORM,"s390x-linux")))
default_platform = VG_PLATFORM;
else
barf("Unknown VG_PLATFORM '%s'", VG_PLATFORM);
/* Work out what platform to use, or use the default platform if
not possible. */
if (clientname == NULL) {
VG_(debugLog)(1, "launcher",
"no client specified, defaulting platform to '%s'\n",
default_platform);
platform = default_platform;
} else if ((platform = select_platform(clientname)) != NULL) {
VG_(debugLog)(1, "launcher", "selected platform '%s'\n", platform);
} else {
VG_(debugLog)(1, "launcher",
"no platform detected, defaulting platform to '%s'\n",
default_platform);
platform = default_platform;
}
/* Figure out the name of this executable (viz, the launcher), so
we can tell stage2. stage2 will use the name for recursive
invocations of valgrind on child processes. */
memset(launcher_name, 0, PATH_MAX+1);
r = readlink("/proc/self/exe", launcher_name, PATH_MAX);
if (r == -1) {
/* If /proc/self/exe can't be followed, don't give up. Instead
continue with an empty string for VALGRIND_LAUNCHER. In the
sys_execve wrapper, this is tested, and if found to be empty,
fail the execve. */
fprintf(stderr, "valgrind: warning (non-fatal): "
"readlink(\"/proc/self/exe\") failed.\n");
fprintf(stderr, "valgrind: continuing, however --trace-children=yes "
"will not work.\n");
}
/* tediously augment the env: VALGRIND_LAUNCHER=launcher_name */
new_line = malloc(strlen(VALGRIND_LAUNCHER) + 1
+ strlen(launcher_name) + 1);
if (new_line == NULL)
barf("malloc of new_line failed.");
strcpy(new_line, VALGRIND_LAUNCHER);
strcat(new_line, "=");
strcat(new_line, launcher_name);
for (j = 0; envp[j]; j++)
;
new_env = malloc((j+2) * sizeof(char*));
if (new_env == NULL)
barf("malloc of new_env failed.");
for (i = 0; i < j; i++)
new_env[i] = envp[i];
new_env[i++] = new_line;
new_env[i++] = NULL;
assert(i == j+2);
/* Establish the correct VALGRIND_LIB. */
cp = getenv(VALGRIND_LIB);
if (cp != NULL)
valgrind_lib = cp;
/* Build the stage2 invocation, and execve it. Bye! */
toolfile = malloc(strlen(valgrind_lib) + strlen(toolname) + strlen(platform) + 3);
if (toolfile == NULL)
barf("malloc of toolfile failed.");
sprintf(toolfile, "%s/%s-%s", valgrind_lib, toolname, platform);
VG_(debugLog)(1, "launcher", "launching %s\n", toolfile);
execve(toolfile, argv, new_env);
fprintf(stderr, "valgrind: failed to start tool '%s' for platform '%s': %s\n",
toolname, platform, strerror(errno));
exit(1);
}