diff options
Diffstat (limited to 'wrapper.c')
| -rw-r--r-- | wrapper.c | 512 |
1 files changed, 363 insertions, 149 deletions
@@ -2,62 +2,54 @@ * Various trivial helper wrappers around standard functions */ #include "cache.h" +#include "config.h" -static void do_nothing(size_t size) +static int memory_limit_check(size_t size, int gentle) { -} - -static void (*try_to_free_routine)(size_t size) = do_nothing; - -static void memory_limit_check(size_t size) -{ - static int limit = -1; - if (limit == -1) { - const char *env = getenv("GIT_ALLOC_LIMIT"); - limit = env ? atoi(env) * 1024 : 0; + static size_t limit = 0; + if (!limit) { + limit = git_env_ulong("GIT_ALLOC_LIMIT", 0); + if (!limit) + limit = SIZE_MAX; } - if (limit && size > limit) - die("attempting to allocate %"PRIuMAX" over limit %d", - (intmax_t)size, limit); -} - -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; + 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) { - try_to_free_routine(strlen(str) + 1); - ret = strdup(str); - if (!ret) - die("Out of memory, strdup failed"); - } + if (!ret) + die("Out of memory, strdup failed"); return ret; } -void *xmalloc(size_t size) +static void *do_xmalloc(size_t size, int gentle) { void *ret; - memory_limit_check(size); + 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); @@ -65,16 +57,37 @@ void *xmalloc(size_t size) return ret; } -void *xmallocz(size_t size) +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)) - die("Data too large to fit into virtual memory space."); - ret = xmalloc(size + 1); - ((char*)ret)[size] = 0; + 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, @@ -96,18 +109,12 @@ void *xrealloc(void *ptr, size_t size) { void *ret; - memory_limit_check(size); + 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"); - } + if (!ret) + die("Out of memory, realloc failed"); return ret; } @@ -115,28 +122,92 @@ void *xcalloc(size_t nmemb, size_t size) { void *ret; - memory_limit_check(size * nmemb); + 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"); - } + 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 absense of bugs, large chunks can result in bad latencies when + * 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. */ -#define MAX_IO_SIZE (8*1024*1024) +#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() @@ -150,8 +221,12 @@ ssize_t xread(int fd, void *buf, size_t len) len = MAX_IO_SIZE; while (1) { nr = read(fd, buf, len); - if ((nr < 0) && (errno == EAGAIN || errno == EINTR)) - continue; + if (nr < 0) { + if (errno == EINTR) + continue; + if (handle_nonblock(fd, POLLIN, errno)) + continue; + } return nr; } } @@ -168,6 +243,29 @@ ssize_t xwrite(int fd, const void *buf, size_t len) 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; @@ -214,6 +312,26 @@ ssize_t write_in_full(int fd, const void *buf, size_t count) 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); @@ -222,6 +340,27 @@ int xdup(int fd) 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); @@ -230,60 +369,65 @@ FILE *xfdopen(int fd, const char *mode) return stream; } -int xmkstemp(char *template) +FILE *fopen_for_writing(const char *path) { - int fd; - char origtemplate[PATH_MAX]; - strlcpy(origtemplate, template, sizeof(origtemplate)); - - fd = mkstemp(template); - if (fd < 0) { - int saved_errno = errno; - const char *nonrelative_template; + FILE *ret = fopen(path, "w"); - if (strlen(template) != strlen(origtemplate)) - template = origtemplate; - - nonrelative_template = absolute_path(template); - errno = saved_errno; - die_errno("Unable to create temporary file '%s'", - nonrelative_template); + if (!ret && errno == EPERM) { + if (!unlink(path)) + ret = fopen(path, "w"); + else + errno = EPERM; } - return fd; + return ret; } -/* git_mkstemp() - create tmp file honoring TMPDIR variable */ -int git_mkstemp(char *path, size_t len, const char *template) +static void warn_on_inaccessible(const char *path) { - const char *tmp; - size_t n; + warning_errno(_("unable to access '%s'"), path); +} - tmp = getenv("TMPDIR"); - if (!tmp) - tmp = "/tmp"; - n = snprintf(path, len, "%s/%s", tmp, template); - if (len <= n) { - errno = ENAMETOOLONG; +int warn_on_fopen_errors(const char *path) +{ + if (errno != ENOENT && errno != ENOTDIR) { + warn_on_inaccessible(path); return -1; } - return mkstemp(path); + + return 0; } -/* git_mkstemps() - create tmp file with suffix honoring TMPDIR variable. */ -int git_mkstemps(char *path, size_t len, const char *template, int suffix_len) +FILE *fopen_or_warn(const char *path, const char *mode) { - const char *tmp; - size_t n; + FILE *fp = fopen(path, mode); - tmp = getenv("TMPDIR"); - if (!tmp) - tmp = "/tmp"; - n = snprintf(path, len, "%s/%s", tmp, template); - if (len <= n) { - errno = ENAMETOOLONG; - return -1; + 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 mkstemps(path, suffix_len); + return fd; } /* Adapted from libiberty's mkstemp.c. */ @@ -297,21 +441,23 @@ int git_mkstemps_mode(char *pattern, int suffix_len, int mode) "abcdefghijklmnopqrstuvwxyz" "ABCDEFGHIJKLMNOPQRSTUVWXYZ" "0123456789"; - static const int num_letters = 62; + 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 *template; + char *filename_template; size_t len; int fd, count; len = strlen(pattern); - if (len < 6 + suffix_len) { + if (len < num_x + suffix_len) { errno = EINVAL; return -1; } - if (strncmp(&pattern[len - 6 - suffix_len], "XXXXXX", 6)) { + if (strncmp(&pattern[len - num_x - suffix_len], x_pattern, num_x)) { errno = EINVAL; return -1; } @@ -321,17 +467,16 @@ int git_mkstemps_mode(char *pattern, int suffix_len, int mode) * Try TMP_MAX different filenames. */ gettimeofday(&tv, NULL); - value = ((size_t)(tv.tv_usec << 16)) ^ tv.tv_sec ^ getpid(); - template = &pattern[len - 6 - suffix_len]; + 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. */ - template[0] = letters[v % num_letters]; v /= num_letters; - template[1] = letters[v % num_letters]; v /= num_letters; - template[2] = letters[v % num_letters]; v /= num_letters; - template[3] = letters[v % num_letters]; v /= num_letters; - template[4] = letters[v % num_letters]; v /= num_letters; - template[5] = letters[v % num_letters]; v /= num_letters; + 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) @@ -360,26 +505,21 @@ int git_mkstemp_mode(char *pattern, int mode) return git_mkstemps_mode(pattern, 0, mode); } -int gitmkstemps(char *pattern, int suffix_len) -{ - return git_mkstemps_mode(pattern, suffix_len, 0600); -} - -int xmkstemp_mode(char *template, int mode) +int xmkstemp_mode(char *filename_template, int mode) { int fd; char origtemplate[PATH_MAX]; - strlcpy(origtemplate, template, sizeof(origtemplate)); + strlcpy(origtemplate, filename_template, sizeof(origtemplate)); - fd = git_mkstemp_mode(template, mode); + fd = git_mkstemp_mode(filename_template, mode); if (fd < 0) { int saved_errno = errno; const char *nonrelative_template; - if (!template[0]) - template = origtemplate; + if (!filename_template[0]) + filename_template = origtemplate; - nonrelative_template = absolute_path(template); + nonrelative_template = absolute_path(filename_template); errno = saved_errno; die_errno("Unable to create temporary file '%s'", nonrelative_template); @@ -389,17 +529,29 @@ int xmkstemp_mode(char *template, int mode) static int warn_if_unremovable(const char *op, const char *file, int rc) { - if (rc < 0) { - int err = errno; - if (ENOENT != err) { - warning("unable to %s %s: %s", - op, file, strerror(errno)); - errno = err; - } - } + 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)); @@ -415,15 +567,10 @@ int remove_or_warn(unsigned int mode, const char *file) return S_ISGITLINK(mode) ? rmdir_or_warn(file) : unlink_or_warn(file); } -void warn_on_inaccessible(const char *path) -{ - warning(_("unable to access '%s': %s"), path, strerror(errno)); -} - static int access_error_is_ok(int err, unsigned flag) { - return err == ENOENT || err == ENOTDIR || - ((flag & ACCESS_EACCES_OK) && err == EACCES); + return (is_missing_file_error(err) || + ((flag & ACCESS_EACCES_OK) && err == EACCES)); } int access_or_warn(const char *path, int mode, unsigned flag) @@ -442,14 +589,81 @@ int access_or_die(const char *path, int mode, unsigned flag) return ret; } -struct passwd *xgetpwuid_self(void) +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 passwd *pw; + struct stat st; + + if (stat(filename, &st) < 0) { + if (errno == ENOENT) + return 1; + die_errno(_("could not stat %s"), filename); + } - errno = 0; - pw = getpwuid(getuid()); - if (!pw) - die(_("unable to look up current user in the passwd file: %s"), - errno ? strerror(errno) : _("no such user")); - return pw; + return !st.st_size; } |