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/*
* Read /proc/self/cmdline and /proc/self/exe such that it can be tested
* whether Valgrind intercepts the system calls that access these pseudo-files
* properly on Linux and whether Valgrind does not modify the behavior of
* accessing these files on other operating systems.
*/
#define _ATFILE_SOURCE
#include <ctype.h>
#include <errno.h>
#include <fcntl.h>
#include <stdio.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <string.h>
#include <unistd.h>
#include "../../config.h"
static void test_cmdline(const char* const cwd, const char* const label,
const char* const path)
{
int fd, n;
char ch;
fprintf(stderr, "%s:\n", label);
fd = open(path, 0);
if (fd >= 0)
{
while ((n = read(fd, &ch, 1)) > 0)
{
if (ch == '\\')
fprintf(stderr, "\\\\");
else if (ch == 0)
fprintf(stderr, "\\0");
else if (isprint((unsigned)ch))
fprintf(stderr, "%c", ch);
else
fprintf(stderr, "\\0%o", ch);
}
fprintf(stderr, "\n");
close(fd);
}
else
perror("open()");
}
static void test_readlink(const char* const cwd, const char* const label,
const char* const path)
{
char buf[512];
const char* p;
int n;
if ((n = readlink(path, buf, sizeof(buf) - 1)) >= 0)
{
buf[n] = 0;
p = buf;
if (strncmp(buf, cwd, strlen(cwd)) == 0)
p += strlen(cwd);
fprintf(stderr, "Result of readlink(\"%s\"): %s\n", label, p);
}
else
perror("readlink");
}
static void test_readlinkat(const char* const cwd, const char* const label,
const char* const path)
{
#if HAVE_READLINKAT
char buf[512];
const char* p;
int n;
if ((n = readlinkat(AT_FDCWD, path, buf, sizeof(buf) - 1)) >= 0)
{
buf[n] = 0;
p = buf;
if (strncmp(buf, cwd, strlen(cwd)) == 0)
p += strlen(cwd);
fprintf(stderr, "Result of readlinkat(\"%s\"): %s\n", label, p);
}
else
perror("readlinkat");
#else
errno = ENOSYS;
perror("readlinkat");
#endif
}
int main(int argc, char** argv)
{
char cwd[512];
char path[512];
cwd[0] = 0;
if (! getcwd(cwd, sizeof(cwd)))
perror("getcwd");
strcat(cwd, "/");
snprintf(path, sizeof(path), "/proc/%ld/cmdline", (long) getpid());
test_cmdline(cwd, "/proc/self/cmdline", "/proc/self/cmdline");
test_cmdline(cwd, "/proc/<pid>/cmdline", path);
snprintf(path, sizeof(path), "/proc/%ld/exe", (long) getpid());
test_readlink(cwd, "/proc/self/exe", "/proc/self/exe");
test_readlink(cwd, "/proc/<pid>/exe", path);
test_readlinkat(cwd, "/proc/self/exe", "/proc/self/exe");
test_readlinkat(cwd, "/proc/<pid>/exe", path);
return 0;
}
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