aboutsummaryrefslogtreecommitdiff
diff options
context:
space:
mode:
-rw-r--r--Makefile4
-rw-r--r--compat/posix.h14
-rw-r--r--compat/writev.c44
-rw-r--r--config.mak.uname2
-rw-r--r--meson.build1
5 files changed, 65 insertions, 0 deletions
diff --git a/Makefile b/Makefile
index 8aa489f3b6..61c7dff942 100644
--- a/Makefile
+++ b/Makefile
@@ -2015,6 +2015,10 @@ ifdef NO_PREAD
COMPAT_CFLAGS += -DNO_PREAD
COMPAT_OBJS += compat/pread.o
endif
+ifdef NO_WRITEV
+ COMPAT_CFLAGS += -DNO_WRITEV
+ COMPAT_OBJS += compat/writev.o
+endif
ifdef NO_FAST_WORKING_DIRECTORY
BASIC_CFLAGS += -DNO_FAST_WORKING_DIRECTORY
endif
diff --git a/compat/posix.h b/compat/posix.h
index 245386fa4a..3c611d2736 100644
--- a/compat/posix.h
+++ b/compat/posix.h
@@ -137,6 +137,9 @@
#include <sys/socket.h>
#include <sys/ioctl.h>
#include <sys/statvfs.h>
+#ifndef NO_WRITEV
+#include <sys/uio.h>
+#endif
#include <termios.h>
#ifndef NO_SYS_SELECT_H
#include <sys/select.h>
@@ -323,6 +326,17 @@ int git_lstat(const char *, struct stat *);
ssize_t git_pread(int fd, void *buf, size_t count, off_t offset);
#endif
+#ifdef NO_WRITEV
+#define writev git_writev
+#define iovec git_iovec
+struct git_iovec {
+ void *iov_base;
+ size_t iov_len;
+};
+
+ssize_t git_writev(int fd, const struct iovec *iov, int iovcnt);
+#endif
+
#ifdef NO_SETENV
#define setenv gitsetenv
int gitsetenv(const char *, const char *, int);
diff --git a/compat/writev.c b/compat/writev.c
new file mode 100644
index 0000000000..3a94870a2f
--- /dev/null
+++ b/compat/writev.c
@@ -0,0 +1,44 @@
+#include "../git-compat-util.h"
+#include "../wrapper.h"
+
+ssize_t git_writev(int fd, const struct iovec *iov, int iovcnt)
+{
+ size_t total_written = 0;
+ size_t sum = 0;
+
+ /*
+ * According to writev(3p), the syscall shall error with EINVAL in case
+ * the sum of `iov_len` overflows `ssize_t`.
+ */
+ for (int i = 0; i < iovcnt; i++) {
+ if (iov[i].iov_len > maximum_signed_value_of_type(ssize_t) ||
+ iov[i].iov_len + sum > maximum_signed_value_of_type(ssize_t)) {
+ errno = EINVAL;
+ return -1;
+ }
+
+ sum += iov[i].iov_len;
+ }
+
+ for (int i = 0; i < iovcnt; i++) {
+ const char *bytes = iov[i].iov_base;
+ size_t iovec_written = 0;
+
+ while (iovec_written < iov[i].iov_len) {
+ ssize_t bytes_written = xwrite(fd, bytes + iovec_written,
+ iov[i].iov_len - iovec_written);
+ if (bytes_written < 0) {
+ if (total_written)
+ goto out;
+ return bytes_written;
+ }
+ if (!bytes_written)
+ goto out;
+ iovec_written += bytes_written;
+ total_written += bytes_written;
+ }
+ }
+
+out:
+ return (ssize_t) total_written;
+}
diff --git a/config.mak.uname b/config.mak.uname
index 3c35ae33a3..8e66a1cc0a 100644
--- a/config.mak.uname
+++ b/config.mak.uname
@@ -457,6 +457,7 @@ ifeq ($(uname_S),Windows)
SANE_TOOL_PATH ?= $(msvc_bin_dir_msys)
HAVE_ALLOCA_H = YesPlease
NO_PREAD = YesPlease
+ NO_WRITEV = YesPlease
NEEDS_CRYPTO_WITH_SSL = YesPlease
NO_LIBGEN_H = YesPlease
NO_POLL = YesPlease
@@ -672,6 +673,7 @@ ifeq ($(uname_S),MINGW)
pathsep = ;
HAVE_ALLOCA_H = YesPlease
NO_PREAD = YesPlease
+ NO_WRITEV = YesPlease
NEEDS_CRYPTO_WITH_SSL = YesPlease
NO_LIBGEN_H = YesPlease
NO_POLL = YesPlease
diff --git a/meson.build b/meson.build
index dd52efd1c8..f1cd89efc7 100644
--- a/meson.build
+++ b/meson.build
@@ -1405,6 +1405,7 @@ checkfuncs = {
'initgroups' : [],
'strtoumax' : ['strtoumax.c', 'strtoimax.c'],
'pread' : ['pread.c'],
+ 'writev' : ['writev.c'],
}
if host_machine.system() == 'windows'