merge(third_party/git): Merge squashed git subtree at v2.23.0 r/373

Merge commit '1b593e1ea4d2af0f6444d9a7788d5d99abd6fde5' as 'third_party/git'

1 files changed, 705 insertions, 0 deletions

diff --git a/third_party/git/wrapper.c b/third_party/git/wrapper.c
new file mode 100644
index 000000000000..1e45ab7b9274
--- /dev/null
+++ b/third_party/git/wrapper.c
@@ -0,0 +1,705 @@
+/*
+ * 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 = ((uint64_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)
+		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;
+}