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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 14:47:53 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 14:47:53 +0000
commitc8bae7493d2f2910b57f13ded012e86bdcfb0532 (patch)
tree24e09d9f84dec336720cf393e156089ca2835791 /wrapper.c
parentInitial commit. (diff)
downloadgit-upstream.tar.xz
git-upstream.zip
Adding upstream version 1:2.39.2.upstream/1%2.39.2upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to '')
-rw-r--r--wrapper.c830
1 files changed, 830 insertions, 0 deletions
diff --git a/wrapper.c b/wrapper.c
new file mode 100644
index 0000000..299d648
--- /dev/null
+++ b/wrapper.c
@@ -0,0 +1,830 @@
+/*
+ * Various trivial helper wrappers around standard functions
+ */
+#include "cache.h"
+#include "config.h"
+
+static intmax_t count_fsync_writeout_only;
+static intmax_t count_fsync_hardware_flush;
+
+#ifdef HAVE_RTLGENRANDOM
+/* This is required to get access to RtlGenRandom. */
+#define SystemFunction036 NTAPI SystemFunction036
+#include <NTSecAPI.h>
+#undef SystemFunction036
+#endif
+
+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;
+}
+
+void xsetenv(const char *name, const char *value, int overwrite)
+{
+ if (setenv(name, value, overwrite))
+ die_errno(_("could not setenv '%s'"), name ? name : "(null)");
+}
+
+/**
+ * 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_CREAT | O_EXCL)) == (O_CREAT | O_EXCL))
+ die_errno(_("unable to create '%s'"), path);
+ else 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)
+ 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;
+ 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.
+ */
+ filename_template = &pattern[len - num_x - suffix_len];
+ for (count = 0; count < TMP_MAX; ++count) {
+ int i;
+ uint64_t v;
+ if (csprng_bytes(&v, sizeof(v)) < 0)
+ return error_errno("unable to get random bytes for temporary file");
+
+ /* 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;
+ }
+ /* 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;
+}
+
+/*
+ * Some platforms return EINTR from fsync. Since fsync is invoked in some
+ * cases by a wrapper that dies on failure, do not expose EINTR to callers.
+ */
+static int fsync_loop(int fd)
+{
+ int err;
+
+ do {
+ err = fsync(fd);
+ } while (err < 0 && errno == EINTR);
+ return err;
+}
+
+int git_fsync(int fd, enum fsync_action action)
+{
+ switch (action) {
+ case FSYNC_WRITEOUT_ONLY:
+ count_fsync_writeout_only += 1;
+
+#ifdef __APPLE__
+ /*
+ * On macOS, fsync just causes filesystem cache writeback but
+ * does not flush hardware caches.
+ */
+ return fsync_loop(fd);
+#endif
+
+#ifdef HAVE_SYNC_FILE_RANGE
+ /*
+ * On linux 2.6.17 and above, sync_file_range is the way to
+ * issue a writeback without a hardware flush. An offset of
+ * 0 and size of 0 indicates writeout of the entire file and the
+ * wait flags ensure that all dirty data is written to the disk
+ * (potentially in a disk-side cache) before we continue.
+ */
+
+ return sync_file_range(fd, 0, 0, SYNC_FILE_RANGE_WAIT_BEFORE |
+ SYNC_FILE_RANGE_WRITE |
+ SYNC_FILE_RANGE_WAIT_AFTER);
+#endif
+
+#ifdef fsync_no_flush
+ return fsync_no_flush(fd);
+#endif
+
+ errno = ENOSYS;
+ return -1;
+
+ case FSYNC_HARDWARE_FLUSH:
+ count_fsync_hardware_flush += 1;
+
+ /*
+ * On macOS, a special fcntl is required to really flush the
+ * caches within the storage controller. As of this writing,
+ * this is a very expensive operation on Apple SSDs.
+ */
+#ifdef __APPLE__
+ return fcntl(fd, F_FULLFSYNC);
+#else
+ return fsync_loop(fd);
+#endif
+ default:
+ BUG("unexpected git_fsync(%d) call", action);
+ }
+}
+
+static void log_trace_fsync_if(const char *key, intmax_t value)
+{
+ if (value)
+ trace2_data_intmax("fsync", the_repository, key, value);
+}
+
+void trace_git_fsync_stats(void)
+{
+ log_trace_fsync_if("fsync/writeout-only", count_fsync_writeout_only);
+ log_trace_fsync_if("fsync/hardware-flush", count_fsync_hardware_flush);
+}
+
+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
+}
+
+int csprng_bytes(void *buf, size_t len)
+{
+#if defined(HAVE_ARC4RANDOM) || defined(HAVE_ARC4RANDOM_LIBBSD)
+ /* This function never returns an error. */
+ arc4random_buf(buf, len);
+ return 0;
+#elif defined(HAVE_GETRANDOM)
+ ssize_t res;
+ char *p = buf;
+ while (len) {
+ res = getrandom(p, len, 0);
+ if (res < 0)
+ return -1;
+ len -= res;
+ p += res;
+ }
+ return 0;
+#elif defined(HAVE_GETENTROPY)
+ int res;
+ char *p = buf;
+ while (len) {
+ /* getentropy has a maximum size of 256 bytes. */
+ size_t chunk = len < 256 ? len : 256;
+ res = getentropy(p, chunk);
+ if (res < 0)
+ return -1;
+ len -= chunk;
+ p += chunk;
+ }
+ return 0;
+#elif defined(HAVE_RTLGENRANDOM)
+ if (!RtlGenRandom(buf, len))
+ return -1;
+ return 0;
+#elif defined(HAVE_OPENSSL_CSPRNG)
+ int res = RAND_bytes(buf, len);
+ if (res == 1)
+ return 0;
+ if (res == -1)
+ errno = ENOTSUP;
+ else
+ errno = EIO;
+ return -1;
+#else
+ ssize_t res;
+ char *p = buf;
+ int fd, err;
+ fd = open("/dev/urandom", O_RDONLY);
+ if (fd < 0)
+ return -1;
+ while (len) {
+ res = xread(fd, p, len);
+ if (res < 0) {
+ err = errno;
+ close(fd);
+ errno = err;
+ return -1;
+ }
+ len -= res;
+ p += res;
+ }
+ close(fd);
+ return 0;
+#endif
+}