X-Git-Url: https://www.chiark.greenend.org.uk/ucgi/~ianmdlvl/git?a=blobdiff_plain;f=src%2Fshared%2Futil.c;h=dc1bc39ac710b50f4f52cd171674bd053d3b20ae;hb=0c2576ef74a9f9b96519cdcb7f9c01742d8255e2;hp=1d67abe58f4834a1f730dd71eca9265ed654167b;hpb=97768fc5746ea97cb2d3ac6854b4fc7ce1c14f24;p=elogind.git diff --git a/src/shared/util.c b/src/shared/util.c index 1d67abe58..dc1bc39ac 100644 --- a/src/shared/util.c +++ b/src/shared/util.c @@ -695,7 +695,7 @@ int get_process_cmdline(pid_t pid, size_t max_length, bool comm_fallback, char * } /* Kernel threads have no argv[] */ - if (r == NULL || r[0] == 0) { + if (isempty(r)) { _cleanup_free_ char *t = NULL; int h; @@ -2521,8 +2521,36 @@ int dev_urandom(void *p, size_t n) { return 0; } -void random_bytes(void *p, size_t n) { +void initialize_srand(void) { static bool srand_called = false; + unsigned x; +#ifdef HAVE_SYS_AUXV_H + void *auxv; +#endif + + if (srand_called) + return; + + x = 0; + +#ifdef HAVE_SYS_AUXV_H + /* The kernel provides us with a bit of entropy in auxv, so + * let's try to make use of that to seed the pseudo-random + * generator. It's better than nothing... */ + + auxv = (void*) getauxval(AT_RANDOM); + if (auxv) + x ^= *(unsigned*) auxv; +#endif + + x ^= (unsigned) now(CLOCK_REALTIME); + x ^= (unsigned) gettid(); + + srand(x); + srand_called = true; +} + +void random_bytes(void *p, size_t n) { uint8_t *q; int r; @@ -2533,28 +2561,7 @@ void random_bytes(void *p, size_t n) { /* If some idiot made /dev/urandom unavailable to us, he'll * get a PRNG instead. */ - if (!srand_called) { - unsigned x = 0; - -#ifdef HAVE_SYS_AUXV_H - /* The kernel provides us with a bit of entropy in - * auxv, so let's try to make use of that to seed the - * pseudo-random generator. It's better than - * nothing... */ - - void *auxv; - - auxv = (void*) getauxval(AT_RANDOM); - if (auxv) - x ^= *(unsigned*) auxv; -#endif - - x ^= (unsigned) now(CLOCK_REALTIME); - x ^= (unsigned) gettid(); - - srand(x); - srand_called = true; - } + initialize_srand(); for (q = p; q < (uint8_t*) p + n; q ++) *q = rand(); @@ -3172,7 +3179,8 @@ char *replace_env(const char *format, char **env) { case CURLY: if (*e == '{') { - if (!(k = strnappend(r, word, e-word-1))) + k = strnappend(r, word, e-word-1); + if (!k) goto fail; free(r); @@ -3182,7 +3190,8 @@ char *replace_env(const char *format, char **env) { state = VARIABLE; } else if (*e == '$') { - if (!(k = strnappend(r, word, e-word))) + k = strnappend(r, word, e-word); + if (!k) goto fail; free(r); @@ -3214,7 +3223,8 @@ char *replace_env(const char *format, char **env) { } } - if (!(k = strnappend(r, word, e-word))) + k = strnappend(r, word, e-word); + if (!k) goto fail; free(r); @@ -6977,14 +6987,14 @@ int is_symlink(const char *path) { int is_dir(const char* path, bool follow) { struct stat st; + int r; - if (follow) { - if (stat(path, &st) < 0) - return -errno; - } else { - if (lstat(path, &st) < 0) - return -errno; - } + if (follow) + r = stat(path, &st); + else + r = lstat(path, &st); + if (r < 0) + return -errno; return !!S_ISDIR(st.st_mode); }