Add a safe wrapper for write and fix some warnings

[i3/i3] / libi3 / safewrappers.c

diff --git a/libi3/safewrappers.c b/libi3/safewrappers.c
index 2403578dc41da66bd32ce17f4a7d4f455255ab96..6acf3109c553876e1fb7782bb011b0b435ace49a 100644 (file)
--- a/libi3/safewrappers.c
+++ b/libi3/safewrappers.c
@@ -2,18 +2,18 @@
  * vim:ts=4:sw=4:expandtab
  *
  * i3 - an improved dynamic tiling window manager
- *
- * © 2009-2011 Michael Stapelberg and contributors
- *
- * See file LICENSE for license information.
+ * © 2009-2011 Michael Stapelberg and contributors (see also: LICENSE)
  *
  */
 #include <string.h>
 #include <stdlib.h>
 #include <stdarg.h>
+#include <unistd.h>
 #include <stdio.h>
 #include <err.h>
+#include <errno.h>
 
+#include "libi3.h"
 
 /*
  * The s* functions (safe) are wrappers around malloc, strdup, …, which exits if one of
@@ -58,3 +58,30 @@ int sasprintf(char **strp, const char *fmt, ...) {
     va_end(args);
     return result;
 }
+
+ssize_t writeall(int fd, const void *buf, size_t count) {
+    int written = 0;
+    ssize_t n = 0;
+
+    while (written < count) {
+        n = write(fd, buf + written, count - written);
+        if (n == -1) {
+            if (errno == EINTR || errno == EAGAIN)
+                continue;
+            return n;
+        }
+        written += n;
+    }
+
+    return written;
+}
+
+ssize_t swrite(int fd, const void *buf, size_t count) {
+    ssize_t n;
+
+    n = writeall(fd, buf, count);
+    if (n == -1)
+        err(EXIT_FAILURE, "Failed to write %d", fd);
+    else
+        return n;
+}