1 /*
2 * Read /proc/self/cmdline and /proc/self/exe such that it can be tested
3 * whether Valgrind intercepts the system calls that access these pseudo-files
4 * properly on Linux and whether Valgrind does not modify the behavior of
5 * accessing these files on other operating systems.
6 */
7
8 #define _ATFILE_SOURCE
9
10 #include <ctype.h>
11 #include <errno.h>
12 #include <fcntl.h>
13 #include <stdio.h>
14 #include <sys/types.h>
15 #include <sys/stat.h>
16 #include <string.h>
17 #include <unistd.h>
18 #include "../../config.h"
19
test_cmdline(const char * const cwd,const char * const label,const char * const path)20 static void test_cmdline(const char* const cwd, const char* const label,
21 const char* const path)
22 {
23 int fd, n;
24 char ch;
25
26 fprintf(stderr, "%s:\n", label);
27 fd = open(path, 0);
28 if (fd >= 0)
29 {
30 while ((n = read(fd, &ch, 1)) > 0)
31 {
32 if (ch == '\\')
33 fprintf(stderr, "\\\\");
34 else if (ch == 0)
35 fprintf(stderr, "\\0");
36 else if (isprint((unsigned)ch))
37 fprintf(stderr, "%c", ch);
38 else
39 fprintf(stderr, "\\0%o", ch);
40 }
41 fprintf(stderr, "\n");
42 close(fd);
43 }
44 else
45 perror("open()");
46 }
47
test_readlink(const char * const cwd,const char * const label,const char * const path)48 static void test_readlink(const char* const cwd, const char* const label,
49 const char* const path)
50 {
51 char buf[512];
52 const char* p;
53 int n;
54
55 if ((n = readlink(path, buf, sizeof(buf) - 1)) >= 0)
56 {
57 buf[n] = 0;
58 p = buf;
59 if (strncmp(buf, cwd, strlen(cwd)) == 0)
60 p += strlen(cwd);
61 fprintf(stderr, "Result of readlink(\"%s\"): %s\n", label, p);
62 }
63 else
64 perror("readlink");
65 }
66
test_readlinkat(const char * const cwd,const char * const label,const char * const path)67 static void test_readlinkat(const char* const cwd, const char* const label,
68 const char* const path)
69 {
70 #if HAVE_READLINKAT
71 char buf[512];
72 const char* p;
73 int n;
74
75 if ((n = readlinkat(AT_FDCWD, path, buf, sizeof(buf) - 1)) >= 0)
76 {
77 buf[n] = 0;
78 p = buf;
79 if (strncmp(buf, cwd, strlen(cwd)) == 0)
80 p += strlen(cwd);
81 fprintf(stderr, "Result of readlinkat(\"%s\"): %s\n", label, p);
82 }
83 else
84 perror("readlinkat");
85 #else
86 errno = ENOSYS;
87 perror("readlinkat");
88 #endif
89 }
90
main(int argc,char ** argv)91 int main(int argc, char** argv)
92 {
93 char cwd[512];
94 char path[512];
95
96 cwd[0] = 0;
97 if (! getcwd(cwd, sizeof(cwd)))
98 perror("getcwd");
99 strcat(cwd, "/");
100
101 snprintf(path, sizeof(path), "/proc/%ld/cmdline", (long) getpid());
102
103 test_cmdline(cwd, "/proc/self/cmdline", "/proc/self/cmdline");
104 test_cmdline(cwd, "/proc/<pid>/cmdline", path);
105
106 snprintf(path, sizeof(path), "/proc/%ld/exe", (long) getpid());
107
108 test_readlink(cwd, "/proc/self/exe", "/proc/self/exe");
109 test_readlink(cwd, "/proc/<pid>/exe", path);
110
111 test_readlinkat(cwd, "/proc/self/exe", "/proc/self/exe");
112 test_readlinkat(cwd, "/proc/<pid>/exe", path);
113
114 return 0;
115 }
116