From 394f88f26dd4a79e33d2dd8397f05be1b240ffd4 Mon Sep 17 00:00:00 2001
From: octo <octo>
Date: Sun, 28 May 2006 15:15:04 +0000
Subject: [PATCH] Added `sread' and `swrite': `read' and `write' like functions
 that assure that all data is written or fail completely..

---
 src/common.c | 55 ++++++++++++++++++++++++++++++++++++++++++++++++++++
 src/common.h | 38 ++++++++++++++++++++++++++++++++++++
 2 files changed, 93 insertions(+)

diff --git a/src/common.c b/src/common.c
index 78be3afc..138b7678 100644
--- a/src/common.c
+++ b/src/common.c
@@ -125,6 +125,61 @@ void sfree (void **ptr)
 }
 #endif
 
+ssize_t sread (int fd, void *buf, size_t count)
+{
+	char    *ptr;
+	size_t   nleft;
+	ssize_t  status;
+
+	ptr   = (char *) buf;
+	nleft = count;
+
+	while (nleft > 0)
+	{
+		status = read (fd, (void *) ptr, nleft);
+
+		if ((status < 0) && ((errno == EAGAIN) || (errno == EINTR)))
+			continue;
+
+		if (status < 0)
+			return (status);
+
+		assert (nleft >= status);
+
+		nleft = nleft - status;
+		ptr   = ptr   + status;
+	}
+
+	return (0);
+}
+
+
+ssize_t swrite (int fd, const void *buf, size_t count)
+{
+	const char *ptr;
+	size_t      nleft;
+	ssize_t     status;
+
+	ptr   = (const char *) buf;
+	nleft = buflen;
+
+	while (nleft > 0)
+	{
+		status = write (fd, (const void *) ptr, nleft);
+
+		if ((status < 0) && ((errno == EAGAIN) || (errno == EINTR)))
+			continue;
+
+		if (status < 0)
+			return (status);
+
+		nleft = nleft - status;
+		ptr   = ptr   + status;
+	}
+
+	return (0);
+}
+
 int strsplit (char *string, char **fields, size_t size)
 {
 	size_t i;
diff --git a/src/common.h b/src/common.h
index 4dc34b07..f6a8e19a 100644
--- a/src/common.h
+++ b/src/common.h
@@ -37,6 +37,44 @@ void sstrncpy(char *d, const char *s, int len);
 char *sstrdup(const char *s);
 void *smalloc(size_t size);
 
+/*
+ * NAME
+ *   sread
+ *
+ * DESCRIPTION
+ *   Reads exactly `n' bytes or failes. Syntax and other behavior is analogous
+ *   to `read(2)'.
+ *
+ * PARAMETERS
+ *   `fd'          File descriptor to write to.
+ *   `buf'         Buffer that is to be written.
+ *   `count'       Numver of bytes in the buffer.
+ *
+ * RETURN VALUE
+ *   Zero upon success or non-zero if an error occured. `errno' is set in this
+ *   case.
+ */
+ssize_t sread (int fd, void *buf, size_t count);
+
+/*
+ * NAME
+ *   swrite
+ *
+ * DESCRIPTION
+ *   Writes exactly `n' bytes or failes. Syntax and other behavior is analogous
+ *   to `write(2)'.
+ *
+ * PARAMETERS
+ *   `fd'          File descriptor to write to.
+ *   `buf'         Buffer that is to be written.
+ *   `count'       Numver of bytes in the buffer.
+ *
+ * RETURN VALUE
+ *   Zero upon success or non-zero if an error occured. `errno' is set in this
+ *   case.
+ */
+ssize_t swrite (int fd, const void *buf, size_t count);
+
 /*
  * NAME
  *   strsplit
-- 
2.30.2