| /* |
| * Various trivial helper wrappers around standard functions |
| */ |
| #include "cache.h" |
| #include "config.h" |
| |
| static void do_nothing(size_t size) |
| { |
| } |
| |
| static void (*try_to_free_routine)(size_t size) = do_nothing; |
| |
| 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; |
| } |
| |
| try_to_free_t set_try_to_free_routine(try_to_free_t routine) |
| { |
| try_to_free_t old = try_to_free_routine; |
| if (!routine) |
| routine = do_nothing; |
| try_to_free_routine = routine; |
| return old; |
| } |
| |
| char *xstrdup(const char *str) |
| { |
| char *ret = strdup(str); |
| if (!ret) { |
| try_to_free_routine(strlen(str) + 1); |
| 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) { |
| try_to_free_routine(size); |
| 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); |
| } |
| |
| void *xrealloc(void *ptr, size_t size) |
| { |
| void *ret; |
| |
| memory_limit_check(size, 0); |
| ret = realloc(ptr, size); |
| if (!ret && !size) |
| ret = realloc(ptr, 1); |
| if (!ret) { |
| try_to_free_routine(size); |
| ret = realloc(ptr, size); |
| if (!ret && !size) |
| ret = realloc(ptr, 1); |
| 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) { |
| try_to_free_routine(nmemb * size); |
| 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 = 62; |
| uint64_t value; |
| struct timeval tv; |
| char *filename_template; |
| size_t len; |
| int fd, count; |
| |
| len = strlen(pattern); |
| |
| if (len < 6 + suffix_len) { |
| errno = EINVAL; |
| return -1; |
| } |
| |
| if (strncmp(&pattern[len - 6 - suffix_len], "XXXXXX", 6)) { |
| errno = EINVAL; |
| return -1; |
| } |
| |
| /* |
| * Replace pattern's XXXXXX characters with randomness. |
| * Try TMP_MAX different filenames. |
| */ |
| gettimeofday(&tv, NULL); |
| value = ((size_t)(tv.tv_usec << 16)) ^ tv.tv_sec ^ getpid(); |
| filename_template = &pattern[len - 6 - suffix_len]; |
| for (count = 0; count < TMP_MAX; ++count) { |
| uint64_t v = value; |
| /* Fill in the random bits. */ |
| filename_template[0] = letters[v % num_letters]; v /= num_letters; |
| filename_template[1] = letters[v % num_letters]; v /= num_letters; |
| filename_template[2] = letters[v % num_letters]; v /= num_letters; |
| filename_template[3] = letters[v % num_letters]; v /= num_letters; |
| filename_template[4] = letters[v % num_letters]; v /= num_letters; |
| filename_template[5] = 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) |
| die("BUG: your snprintf is broken"); |
| if (len >= max) |
| die("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; |
| } |