-
-/*
- * 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.
- */
-static ssize_t xread(int fd, void *buf, size_t len)
-{
- ssize_t nr;
- while (1) {
- nr = read(fd, buf, len);
- if ((nr < 0) && (errno == EAGAIN || errno == EINTR))
- 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.
- */
-static ssize_t xwrite(int fd, const void *buf, size_t len)
-{
- ssize_t nr;
- while (1) {
- nr = write(fd, buf, len);
- 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 total ? total : loaded;
- 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;
-}