| 1 | #include "../git-compat-util.h" |
| 2 | #include "../wrapper.h" |
| 3 | |
| 4 | ssize_t git_writev(int fd, const struct iovec *iov, int iovcnt) |
| 5 | { |
| 6 | size_t total_written = 0; |
| 7 | size_t sum = 0; |
| 8 | |
| 9 | /* |
| 10 | * According to writev(3p), the syscall shall error with EINVAL in case |
| 11 | * the sum of `iov_len` overflows `ssize_t`. |
| 12 | */ |
| 13 | for (int i = 0; i < iovcnt; i++) { |
| 14 | if (iov[i].iov_len > maximum_signed_value_of_type(ssize_t) || |
| 15 | iov[i].iov_len + sum > maximum_signed_value_of_type(ssize_t)) { |
| 16 | errno = EINVAL; |
| 17 | return -1; |
| 18 | } |
| 19 | |
| 20 | sum += iov[i].iov_len; |
| 21 | } |
| 22 | |
| 23 | for (int i = 0; i < iovcnt; i++) { |
| 24 | const char *bytes = iov[i].iov_base; |
| 25 | size_t iovec_written = 0; |
| 26 | |
| 27 | while (iovec_written < iov[i].iov_len) { |
| 28 | ssize_t bytes_written = xwrite(fd, bytes + iovec_written, |
| 29 | iov[i].iov_len - iovec_written); |
| 30 | if (bytes_written < 0) { |
| 31 | if (total_written) |
| 32 | goto out; |
| 33 | return bytes_written; |
| 34 | } |
| 35 | if (!bytes_written) |
| 36 | goto out; |
| 37 | iovec_written += bytes_written; |
| 38 | total_written += bytes_written; |
| 39 | } |
| 40 | } |
| 41 | |
| 42 | out: |
| 43 | return (ssize_t) total_written; |
| 44 | } |