X-Git-Url: http://www.chiark.greenend.org.uk/ucgi/~ianmdlvl/git?p=elogind.git;a=blobdiff_plain;f=src%2Fshared%2Futil.c;h=0f44eb5afe7a8c57c8985a8397747339d4a11c75;hp=502b3675b1d543fec6b082b46f317b4ffeb5f58e;hb=ef309a681f4c761503e4cd4cc6884d7d6ef70436;hpb=af76d302c1e26f916494202f1b3663f15710bdcd;ds=sidebyside diff --git a/src/shared/util.c b/src/shared/util.c index 502b3675b..0f44eb5af 100644 --- a/src/shared/util.c +++ b/src/shared/util.c @@ -1878,9 +1878,6 @@ int open_terminal(const char *name, int mode) { c++; } - if (fd < 0) - return -errno; - r = isatty(fd); if (r < 0) { safe_close(fd); @@ -2077,7 +2074,7 @@ int acquire_terminal( * ended our handle will be dead. It's important that * we do this after sleeping, so that we don't enter * an endless loop. */ - safe_close(fd); + fd = safe_close(fd); } safe_close(notify); @@ -2469,14 +2466,53 @@ char* dirname_malloc(const char *path) { } int dev_urandom(void *p, size_t n) { - _cleanup_close_ int fd; + static int have_syscall = -1; + int r, fd; ssize_t k; + /* Gathers some randomness from the kernel. This call will + * never block, and will always return some data from the + * kernel, regardless if the random pool is fully initialized + * or not. It thus makes no guarantee for the quality of the + * returned entropy, but is good enough for or usual usecases + * of seeding the hash functions for hashtable */ + + /* Use the getrandom() syscall unless we know we don't have + * it, or when the requested size is too large for it. */ + if (have_syscall != 0 || (size_t) (int) n != n) { + r = getrandom(p, n, GRND_NONBLOCK); + if (r == (int) n) { + have_syscall = true; + return 0; + } + + if (r < 0) { + if (errno == ENOSYS) + /* we lack the syscall, continue with + * reading from /dev/urandom */ + have_syscall = false; + else if (errno == EAGAIN) + /* not enough entropy for now. Let's + * remember to use the syscall the + * next time, again, but also read + * from /dev/urandom for now, which + * doesn't care about the current + * amount of entropy. */ + have_syscall = true; + else + return -errno; + } else + /* too short read? */ + return -EIO; + } + fd = open("/dev/urandom", O_RDONLY|O_CLOEXEC|O_NOCTTY); if (fd < 0) return errno == ENOENT ? -ENOSYS : -errno; k = loop_read(fd, p, n, true); + safe_close(fd); + if (k < 0) return (int) k; if ((size_t) k != n) @@ -2485,8 +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; @@ -2497,28 +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(); @@ -3276,7 +3319,7 @@ unsigned columns(void) { c = 0; e = getenv("COLUMNS"); if (e) - safe_atoi(e, &c); + (void) safe_atoi(e, &c); if (c <= 0) c = fd_columns(STDOUT_FILENO); @@ -3310,7 +3353,7 @@ unsigned lines(void) { l = 0; e = getenv("LINES"); if (e) - safe_atou(e, &l); + (void) safe_atou(e, &l); if (l <= 0) l = fd_lines(STDOUT_FILENO); @@ -3911,7 +3954,7 @@ void execute_directory(const char *directory, DIR *d, usec_t timeout, char *argv } } - pids = hashmap_new(NULL, NULL); + pids = hashmap_new(NULL); if (!pids) { log_oom(); _exit(EXIT_FAILURE); @@ -6694,7 +6737,7 @@ int bind_remount_recursive(const char *prefix, bool ro) { path_kill_slashes(cleaned); - done = set_new(string_hash_func, string_compare_func); + done = set_new(&string_hash_ops); if (!done) return -ENOMEM; @@ -6704,7 +6747,7 @@ int bind_remount_recursive(const char *prefix, bool ro) { bool top_autofs = false; char *x; - todo = set_new(string_hash_func, string_compare_func); + todo = set_new(&string_hash_ops); if (!todo) return -ENOMEM; @@ -6936,10 +6979,21 @@ int is_symlink(const char *path) { if (lstat(path, &info) < 0) return -errno; - if (S_ISLNK(info.st_mode)) - return 1; + return !!S_ISLNK(info.st_mode); +} - return 0; +int is_dir(const char* path, bool follow) { + struct stat st; + + if (follow) { + if (stat(path, &st) < 0) + return -errno; + } else { + if (lstat(path, &st) < 0) + return -errno; + } + + return !!S_ISDIR(st.st_mode); } int unquote_first_word(const char **p, char **ret) { @@ -7167,3 +7221,23 @@ int free_and_strdup(char **p, const char *s) { return 0; } + +int sethostname_idempotent(const char *s) { + int r; + char buf[HOST_NAME_MAX + 1] = {}; + + assert(s); + + r = gethostname(buf, sizeof(buf)); + if (r < 0) + return -errno; + + if (streq(buf, s)) + return 0; + + r = sethostname(s, strlen(s)); + if (r < 0) + return -errno; + + return 1; +}