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| /* | |
| * Various trivial helper wrappers around standard functions | |
| */ | |
| #include "cache.h" | |
| #include "config.h" | |
| static int memory_limit_check(size_t size, int gentle) | |
| { | |
| static size_t limit = 0; | |
| if (!limit) { | |
| limit = git_env_ulong("GIT_ALLOC_LIMIT", 0); | |
| if (!limit) | |
| limit = SIZE_MAX; | |
| } | |
| if (size > limit) { | |
| if (gentle) { | |
| error("attempting to allocate %"PRIuMAX" over limit %"PRIuMAX, | |
| (uintmax_t)size, (uintmax_t)limit); | |
| return -1; | |
| } else | |
| die("attempting to allocate %"PRIuMAX" over limit %"PRIuMAX, | |
| (uintmax_t)size, (uintmax_t)limit); | |
| } | |
| return 0; | |
| } | |
| char *xstrdup(const char *str) | |
| { | |
| char *ret = strdup(str); | |
| if (!ret) | |
| die("Out of memory, strdup failed"); | |
| return ret; | |
| } | |
| static void *do_xmalloc(size_t size, int gentle) | |
| { | |
| void *ret; | |
| if (memory_limit_check(size, gentle)) | |
| return NULL; | |
| ret = malloc(size); | |
| if (!ret && !size) | |
| ret = malloc(1); | |
| if (!ret) { | |
| if (!gentle) | |
| die("Out of memory, malloc failed (tried to allocate %lu bytes)", | |
| (unsigned long)size); | |
| else { | |
| error("Out of memory, malloc failed (tried to allocate %lu bytes)", | |
| (unsigned long)size); | |
| return NULL; | |
| } | |
| } | |
| #ifdef XMALLOC_POISON | |
| memset(ret, 0xA5, size); | |
| #endif | |
| return ret; | |
| } | |
| void *xmalloc(size_t size) | |
| { | |
| return do_xmalloc(size, 0); | |
| } | |
| static void *do_xmallocz(size_t size, int gentle) | |
| { | |
| void *ret; | |
| if (unsigned_add_overflows(size, 1)) { | |
| if (gentle) { | |
| error("Data too large to fit into virtual memory space."); | |
| return NULL; | |
| } else | |
| die("Data too large to fit into virtual memory space."); | |
| } | |
| ret = do_xmalloc(size + 1, gentle); | |
| if (ret) | |
| ((char*)ret)[size] = 0; | |
| return ret; | |
| } | |
| void *xmallocz(size_t size) | |
| { | |
| return do_xmallocz(size, 0); | |
| } | |
| void *xmallocz_gently(size_t size) | |
| { | |
| return do_xmallocz(size, 1); | |
| } | |
| /* | |
| * xmemdupz() allocates (len + 1) bytes of memory, duplicates "len" bytes of | |
| * "data" to the allocated memory, zero terminates the allocated memory, | |
| * and returns a pointer to the allocated memory. If the allocation fails, | |
| * the program dies. | |
| */ | |
| void *xmemdupz(const void *data, size_t len) | |
| { | |
| return memcpy(xmallocz(len), data, len); | |
| } | |
| char *xstrndup(const char *str, size_t len) | |
| { | |
| char *p = memchr(str, '\0', len); | |
| return xmemdupz(str, p ? p - str : len); | |
| } | |
| int xstrncmpz(const char *s, const char *t, size_t len) | |
| { | |
| int res = strncmp(s, t, len); | |
| if (res) | |
| return res; | |
| return s[len] == '\0' ? 0 : 1; | |
| } | |
| void *xrealloc(void *ptr, size_t size) | |
| { | |
| void *ret; | |
| if (!size) { | |
| free(ptr); | |
| return xmalloc(0); | |
| } | |
| memory_limit_check(size, 0); | |
| ret = realloc(ptr, size); | |
| if (!ret) | |
| die("Out of memory, realloc failed"); | |
| return ret; | |
| } | |
| void *xcalloc(size_t nmemb, size_t size) | |
| { | |
| void *ret; | |
| if (unsigned_mult_overflows(nmemb, size)) | |
| die("data too large to fit into virtual memory space"); | |
| memory_limit_check(size * nmemb, 0); | |
| ret = calloc(nmemb, size); | |
| if (!ret && (!nmemb || !size)) | |
| ret = calloc(1, 1); | |
| if (!ret) | |
| die("Out of memory, calloc failed"); | |
| return ret; | |
| } | |
| /* | |
| * Limit size of IO chunks, because huge chunks only cause pain. OS X | |
| * 64-bit is buggy, returning EINVAL if len >= INT_MAX; and even in | |
| * the absence of bugs, large chunks can result in bad latencies when | |
| * you decide to kill the process. | |
| * | |
| * We pick 8 MiB as our default, but if the platform defines SSIZE_MAX | |
| * that is smaller than that, clip it to SSIZE_MAX, as a call to | |
| * read(2) or write(2) larger than that is allowed to fail. As the last | |
| * resort, we allow a port to pass via CFLAGS e.g. "-DMAX_IO_SIZE=value" | |
| * to override this, if the definition of SSIZE_MAX given by the platform | |
| * is broken. | |
| */ | |
| #ifndef MAX_IO_SIZE | |
| # define MAX_IO_SIZE_DEFAULT (8*1024*1024) | |
| # if defined(SSIZE_MAX) && (SSIZE_MAX < MAX_IO_SIZE_DEFAULT) | |
| # define MAX_IO_SIZE SSIZE_MAX | |
| # else | |
| # define MAX_IO_SIZE MAX_IO_SIZE_DEFAULT | |
| # endif | |
| #endif | |
| /** | |
| * xopen() is the same as open(), but it die()s if the open() fails. | |
| */ | |
| int xopen(const char *path, int oflag, ...) | |
| { | |
| mode_t mode = 0; | |
| va_list ap; | |
| /* | |
| * va_arg() will have undefined behavior if the specified type is not | |
| * compatible with the argument type. Since integers are promoted to | |
| * ints, we fetch the next argument as an int, and then cast it to a | |
| * mode_t to avoid undefined behavior. | |
| */ | |
| va_start(ap, oflag); | |
| if (oflag & O_CREAT) | |
| mode = va_arg(ap, int); | |
| va_end(ap); | |
| for (;;) { | |
| int fd = open(path, oflag, mode); | |
| if (fd >= 0) | |
| return fd; | |
| if (errno == EINTR) | |
| continue; | |
| if ((oflag & O_RDWR) == O_RDWR) | |
| die_errno(_("could not open '%s' for reading and writing"), path); | |
| else if ((oflag & O_WRONLY) == O_WRONLY) | |
| die_errno(_("could not open '%s' for writing"), path); | |
| else | |
| die_errno(_("could not open '%s' for reading"), path); | |
| } | |
| } | |
| static int handle_nonblock(int fd, short poll_events, int err) | |
| { | |
| struct pollfd pfd; | |
| if (err != EAGAIN && err != EWOULDBLOCK) | |
| return 0; | |
| pfd.fd = fd; | |
| pfd.events = poll_events; | |
| /* | |
| * no need to check for errors, here; | |
| * a subsequent read/write will detect unrecoverable errors | |
| */ | |
| poll(&pfd, 1, -1); | |
| return 1; | |
| } | |
| /* | |
| * xread() is the same a read(), but it automatically restarts read() | |
| * operations with a recoverable error (EAGAIN and EINTR). xread() | |
| * DOES NOT GUARANTEE that "len" bytes is read even if the data is available. | |
| */ | |
| ssize_t xread(int fd, void *buf, size_t len) | |
| { | |
| ssize_t nr; | |
| if (len > MAX_IO_SIZE) | |
| len = MAX_IO_SIZE; | |
| while (1) { | |
| nr = read(fd, buf, len); | |
| if (nr < 0) { | |
| if (errno == EINTR) | |
| continue; | |
| if (handle_nonblock(fd, POLLIN, errno)) | |
| continue; | |
| } | |
| return nr; | |
| } | |
| } | |
| /* | |
| * xwrite() is the same a write(), but it automatically restarts write() | |
| * operations with a recoverable error (EAGAIN and EINTR). xwrite() DOES NOT | |
| * GUARANTEE that "len" bytes is written even if the operation is successful. | |
| */ | |
| ssize_t xwrite(int fd, const void *buf, size_t len) | |
| { | |
| ssize_t nr; | |
| if (len > MAX_IO_SIZE) | |
| len = MAX_IO_SIZE; | |
| while (1) { | |
| nr = write(fd, buf, len); | |
| if (nr < 0) { | |
| if (errno == EINTR) | |
| continue; | |
| if (handle_nonblock(fd, POLLOUT, errno)) | |
| continue; | |
| } | |
| return nr; | |
| } | |
| } | |
| /* | |
| * xpread() is the same as pread(), but it automatically restarts pread() | |
| * operations with a recoverable error (EAGAIN and EINTR). xpread() DOES | |
| * NOT GUARANTEE that "len" bytes is read even if the data is available. | |
| */ | |
| ssize_t xpread(int fd, void *buf, size_t len, off_t offset) | |
| { | |
| ssize_t nr; | |
| if (len > MAX_IO_SIZE) | |
| len = MAX_IO_SIZE; | |
| while (1) { | |
| nr = pread(fd, buf, len, offset); | |
| if ((nr < 0) && (errno == EAGAIN || errno == EINTR)) | |
| continue; | |
| return nr; | |
| } | |
| } | |
| ssize_t read_in_full(int fd, void *buf, size_t count) | |
| { | |
| char *p = buf; | |
| ssize_t total = 0; | |
| while (count > 0) { | |
| ssize_t loaded = xread(fd, p, count); | |
| if (loaded < 0) | |
| return -1; | |
| if (loaded == 0) | |
| return total; | |
| count -= loaded; | |
| p += loaded; | |
| total += loaded; | |
| } | |
| return total; | |
| } | |
| ssize_t write_in_full(int fd, const void *buf, size_t count) | |
| { | |
| const char *p = buf; | |
| ssize_t total = 0; | |
| while (count > 0) { | |
| ssize_t written = xwrite(fd, p, count); | |
| if (written < 0) | |
| return -1; | |
| if (!written) { | |
| errno = ENOSPC; | |
| return -1; | |
| } | |
| count -= written; | |
| p += written; | |
| total += written; | |
| } | |
| return total; | |
| } | |
| ssize_t pread_in_full(int fd, void *buf, size_t count, off_t offset) | |
| { | |
| char *p = buf; | |
| ssize_t total = 0; | |
| while (count > 0) { | |
| ssize_t loaded = xpread(fd, p, count, offset); | |
| if (loaded < 0) | |
| return -1; | |
| if (loaded == 0) | |
| return total; | |
| count -= loaded; | |
| p += loaded; | |
| total += loaded; | |
| offset += loaded; | |
| } | |
| return total; | |
| } | |
| int xdup(int fd) | |
| { | |
| int ret = dup(fd); | |
| if (ret < 0) | |
| die_errno("dup failed"); | |
| return ret; | |
| } | |
| /** | |
| * xfopen() is the same as fopen(), but it die()s if the fopen() fails. | |
| */ | |
| FILE *xfopen(const char *path, const char *mode) | |
| { | |
| for (;;) { | |
| FILE *fp = fopen(path, mode); | |
| if (fp) | |
| return fp; | |
| if (errno == EINTR) | |
| continue; | |
| if (*mode && mode[1] == '+') | |
| die_errno(_("could not open '%s' for reading and writing"), path); | |
| else if (*mode == 'w' || *mode == 'a') | |
| die_errno(_("could not open '%s' for writing"), path); | |
| else | |
| die_errno(_("could not open '%s' for reading"), path); | |
| } | |
| } | |
| FILE *xfdopen(int fd, const char *mode) | |
| { | |
| FILE *stream = fdopen(fd, mode); | |
| if (stream == NULL) | |
| die_errno("Out of memory? fdopen failed"); | |
| return stream; | |
| } | |
| FILE *fopen_for_writing(const char *path) | |
| { | |
| FILE *ret = fopen(path, "w"); | |
| if (!ret && errno == EPERM) { | |
| if (!unlink(path)) | |
| ret = fopen(path, "w"); | |
| else | |
| errno = EPERM; | |
| } | |
| return ret; | |
| } | |
| static void warn_on_inaccessible(const char *path) | |
| { | |
| warning_errno(_("unable to access '%s'"), path); | |
| } | |
| int warn_on_fopen_errors(const char *path) | |
| { | |
| if (errno != ENOENT && errno != ENOTDIR) { | |
| warn_on_inaccessible(path); | |
| return -1; | |
| } | |
| return 0; | |
| } | |
| FILE *fopen_or_warn(const char *path, const char *mode) | |
| { | |
| FILE *fp = fopen(path, mode); | |
| if (fp) | |
| return fp; | |
| warn_on_fopen_errors(path); | |
| return NULL; | |
| } | |
| int xmkstemp(char *filename_template) | |
| { | |
| int fd; | |
| char origtemplate[PATH_MAX]; | |
| strlcpy(origtemplate, filename_template, sizeof(origtemplate)); | |
| fd = mkstemp(filename_template); | |
| if (fd < 0) { | |
| int saved_errno = errno; | |
| const char *nonrelative_template; | |
| if (strlen(filename_template) != strlen(origtemplate)) | |
| filename_template = origtemplate; | |
| nonrelative_template = absolute_path(filename_template); | |
| errno = saved_errno; | |
| die_errno("Unable to create temporary file '%s'", | |
| nonrelative_template); | |
| } | |
| return fd; | |
| } | |
| /* Adapted from libiberty's mkstemp.c. */ | |
| #undef TMP_MAX | |
| #define TMP_MAX 16384 | |
| int git_mkstemps_mode(char *pattern, int suffix_len, int mode) | |
| { | |
| static const char letters[] = | |
| "abcdefghijklmnopqrstuvwxyz" | |
| "ABCDEFGHIJKLMNOPQRSTUVWXYZ" | |
| "0123456789"; | |
| static const int num_letters = ARRAY_SIZE(letters) - 1; | |
| static const char x_pattern[] = "XXXXXX"; | |
| static const int num_x = ARRAY_SIZE(x_pattern) - 1; | |
| uint64_t value; | |
| struct timeval tv; | |
| char *filename_template; | |
| size_t len; | |
| int fd, count; | |
| len = strlen(pattern); | |
| if (len < num_x + suffix_len) { | |
| errno = EINVAL; | |
| return -1; | |
| } | |
| if (strncmp(&pattern[len - num_x - suffix_len], x_pattern, num_x)) { | |
| errno = EINVAL; | |
| return -1; | |
| } | |
| /* | |
| * Replace pattern's XXXXXX characters with randomness. | |
| * Try TMP_MAX different filenames. | |
| */ | |
| gettimeofday(&tv, NULL); | |
| value = ((uint64_t)tv.tv_usec << 16) ^ tv.tv_sec ^ getpid(); | |
| filename_template = &pattern[len - num_x - suffix_len]; | |
| for (count = 0; count < TMP_MAX; ++count) { | |
| uint64_t v = value; | |
| int i; | |
| /* Fill in the random bits. */ | |
| for (i = 0; i < num_x; i++) { | |
| filename_template[i] = letters[v % num_letters]; | |
| v /= num_letters; | |
| } | |
| fd = open(pattern, O_CREAT | O_EXCL | O_RDWR, mode); | |
| if (fd >= 0) | |
| return fd; | |
| /* | |
| * Fatal error (EPERM, ENOSPC etc). | |
| * It doesn't make sense to loop. | |
| */ | |
| if (errno != EEXIST) | |
| break; | |
| /* | |
| * This is a random value. It is only necessary that | |
| * the next TMP_MAX values generated by adding 7777 to | |
| * VALUE are different with (module 2^32). | |
| */ | |
| value += 7777; | |
| } | |
| /* We return the null string if we can't find a unique file name. */ | |
| pattern[0] = '\0'; | |
| return -1; | |
| } | |
| int git_mkstemp_mode(char *pattern, int mode) | |
| { | |
| /* mkstemp is just mkstemps with no suffix */ | |
| return git_mkstemps_mode(pattern, 0, mode); | |
| } | |
| int xmkstemp_mode(char *filename_template, int mode) | |
| { | |
| int fd; | |
| char origtemplate[PATH_MAX]; | |
| strlcpy(origtemplate, filename_template, sizeof(origtemplate)); | |
| fd = git_mkstemp_mode(filename_template, mode); | |
| if (fd < 0) { | |
| int saved_errno = errno; | |
| const char *nonrelative_template; | |
| if (!filename_template[0]) | |
| filename_template = origtemplate; | |
| nonrelative_template = absolute_path(filename_template); | |
| errno = saved_errno; | |
| die_errno("Unable to create temporary file '%s'", | |
| nonrelative_template); | |
| } | |
| return fd; | |
| } | |
| static int warn_if_unremovable(const char *op, const char *file, int rc) | |
| { | |
| int err; | |
| if (!rc || errno == ENOENT) | |
| return 0; | |
| err = errno; | |
| warning_errno("unable to %s '%s'", op, file); | |
| errno = err; | |
| return rc; | |
| } | |
| int unlink_or_msg(const char *file, struct strbuf *err) | |
| { | |
| int rc = unlink(file); | |
| assert(err); | |
| if (!rc || errno == ENOENT) | |
| return 0; | |
| strbuf_addf(err, "unable to unlink '%s': %s", | |
| file, strerror(errno)); | |
| return -1; | |
| } | |
| int unlink_or_warn(const char *file) | |
| { | |
| return warn_if_unremovable("unlink", file, unlink(file)); | |
| } | |
| int rmdir_or_warn(const char *file) | |
| { | |
| return warn_if_unremovable("rmdir", file, rmdir(file)); | |
| } | |
| int remove_or_warn(unsigned int mode, const char *file) | |
| { | |
| return S_ISGITLINK(mode) ? rmdir_or_warn(file) : unlink_or_warn(file); | |
| } | |
| static int access_error_is_ok(int err, unsigned flag) | |
| { | |
| return (is_missing_file_error(err) || | |
| ((flag & ACCESS_EACCES_OK) && err == EACCES)); | |
| } | |
| int access_or_warn(const char *path, int mode, unsigned flag) | |
| { | |
| int ret = access(path, mode); | |
| if (ret && !access_error_is_ok(errno, flag)) | |
| warn_on_inaccessible(path); | |
| return ret; | |
| } | |
| int access_or_die(const char *path, int mode, unsigned flag) | |
| { | |
| int ret = access(path, mode); | |
| if (ret && !access_error_is_ok(errno, flag)) | |
| die_errno(_("unable to access '%s'"), path); | |
| return ret; | |
| } | |
| char *xgetcwd(void) | |
| { | |
| struct strbuf sb = STRBUF_INIT; | |
| if (strbuf_getcwd(&sb)) | |
| die_errno(_("unable to get current working directory")); | |
| return strbuf_detach(&sb, NULL); | |
| } | |
| int xsnprintf(char *dst, size_t max, const char *fmt, ...) | |
| { | |
| va_list ap; | |
| int len; | |
| va_start(ap, fmt); | |
| len = vsnprintf(dst, max, fmt, ap); | |
| va_end(ap); | |
| if (len < 0) | |
| BUG("your snprintf is broken"); | |
| if (len >= max) | |
| BUG("attempt to snprintf into too-small buffer"); | |
| return len; | |
| } | |
| void write_file_buf(const char *path, const char *buf, size_t len) | |
| { | |
| int fd = xopen(path, O_WRONLY | O_CREAT | O_TRUNC, 0666); | |
| if (write_in_full(fd, buf, len) < 0) | |
| die_errno(_("could not write to '%s'"), path); | |
| if (close(fd)) | |
| die_errno(_("could not close '%s'"), path); | |
| } | |
| void write_file(const char *path, const char *fmt, ...) | |
| { | |
| va_list params; | |
| struct strbuf sb = STRBUF_INIT; | |
| va_start(params, fmt); | |
| strbuf_vaddf(&sb, fmt, params); | |
| va_end(params); | |
| strbuf_complete_line(&sb); | |
| write_file_buf(path, sb.buf, sb.len); | |
| strbuf_release(&sb); | |
| } | |
| void sleep_millisec(int millisec) | |
| { | |
| poll(NULL, 0, millisec); | |
| } | |
| int xgethostname(char *buf, size_t len) | |
| { | |
| /* | |
| * If the full hostname doesn't fit in buf, POSIX does not | |
| * specify whether the buffer will be null-terminated, so to | |
| * be safe, do it ourselves. | |
| */ | |
| int ret = gethostname(buf, len); | |
| if (!ret) | |
| buf[len - 1] = 0; | |
| return ret; | |
| } | |
| int is_empty_or_missing_file(const char *filename) | |
| { | |
| struct stat st; | |
| if (stat(filename, &st) < 0) { | |
| if (errno == ENOENT) | |
| return 1; | |
| die_errno(_("could not stat %s"), filename); | |
| } | |
| return !st.st_size; | |
| } | |
| int open_nofollow(const char *path, int flags) | |
| { | |
| #ifdef O_NOFOLLOW | |
| return open(path, flags | O_NOFOLLOW); | |
| #else | |
| struct stat st; | |
| if (lstat(path, &st) < 0) | |
| return -1; | |
| if (S_ISLNK(st.st_mode)) { | |
| errno = ELOOP; | |
| return -1; | |
| } | |
| return open(path, flags); | |
| #endif | |
| } |