Move {read,write}_all functions to a dedicated header

Since these functions are used in both catgets/gencat.c and
malloc/memusage{,stat}.c, it make sense to move them into a dedicated
header where they can be inlined.

Reviewed-by: Siddhesh Poyarekar <siddhesh@sourceware.org>

1 files changed, 66 insertions, 0 deletions

diff --git a/include/unistd_ext.h b/include/unistd_ext.h
new file mode 100644
index 0000000000..8c93bde88b
--- /dev/null
+++ b/include/unistd_ext.h
@@ -0,0 +1,66 @@
+/* unistd.h related helpers.
+   Copyright (C) 2023 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 of the License, or (at your option) any later version.
+
+   The GNU C Library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library; if not, see
+   <https://www.gnu.org/licenses/>.  */
+
+#ifndef _UNISTD_EXT_H
+#define _UNISTD_EXT_H
+
+#include <error.h>
+#include <errno.h>
+#include <libintl.h>
+#include <unistd.h>
+
+/* Helpers used in catgets/gencat.c and malloc/memusage*.c */
+static inline void
+write_all (int fd, const void *buffer, size_t length)
+{
+  const char *p = buffer;
+  const char *end = p + length;
+  while (p < end)
+    {
+      ssize_t ret = write (fd, p, end - p);
+      if (ret < 0)
+	error (EXIT_FAILURE, errno,
+	       gettext ("write of %zu bytes failed after %td: %m"),
+	       length, p - (const char *) buffer);
+
+      if (ret == 0)
+	error (EXIT_FAILURE, 0,
+	       gettext ("write returned 0 after writing %td bytes of %zu"),
+	       p - (const char *) buffer, length);
+      p += ret;
+    }
+}
+
+static inline void
+read_all (int fd, void *buffer, size_t length)
+{
+  char *p = buffer;
+  char *end = p + length;
+  while (p < end)
+    {
+      ssize_t ret = read (fd, p, end - p);
+      if (ret < 0)
+	error (EXIT_FAILURE, errno,
+	       gettext ("read of %zu bytes failed after %td: %m"),
+	       length, p - (char *) buffer);
+
+      p += ret;
+    }
+}
+
+#endif