#include <unistd.h>
#include <errno.h>
#include <stdlib.h>
-#include <stdbool.h>
+HEADER #include <stdbool.h>
#include <sys/stat.h>
#include <fcntl.h>
#include <string.h>
-#include <assert.h>
#include <sys/mman.h>
// Wrapper for `read` that retries on partial reads.
// - -1: error
// - 0: stream ended
// - 1: no problems occured
-PUBLIC_FN ssize_t write_nointr(int fd, void *buf, size_t count, int *last_res) {
+PUBLIC_FN ssize_t write_nointr(int fd, const void *buf, ssize_t count, int *last_res) {
+ if (count == -1) count = strlen(buf);
errno = 0;
size_t done = 0;
while (done < count) {
errno = errno_;
return (r==MAP_FAILED) ? NULL : r;
}
+
+// on error, fd remains unchanged, no matter whether you specified "keep" or not
+HEADER #define JH_OBS_KEEPFD 1
+HEADER #define JH_OBS_BUFFER 2
+PUBLIC_FN int fopen_bistream(FILE **in, FILE **out, int fd, int flags) {
+ // check input
+ if (fd < 0) goto err_out;
+ bool keep = flags & JH_OBS_KEEPFD;
+ bool buffer = flags & JH_OBS_BUFFER;
+
+ // create input FILE*
+ int in_fd = dup(fd);
+ if (in_fd < 0) goto err_out;
+ *in = fdopen(in_fd, "r");
+ if (!*in) { close(in_fd); goto err_out; }
+
+ // create output FILE*
+ int out_fd = keep ? dup(fd) : fd;
+ if (out_fd < 0) goto err_dup_out;
+ *out = fdopen(out_fd, "w");
+ if (!*out) { if (keep) close(out_fd); goto err_dup_out; }
+
+ // avoid buffering data unless the caller really wants it
+ if (!buffer) setbuf(*out, NULL);
+
+ // success!
+ return 0;
+
+
+err_dup_out:
+ fclose(*in);
+err_out:
+ return EAI_SYSTEM;
+}