From: Paul Mackerras <paulus@samba.org>
Date: Sun, 30 Mar 2003 08:26:56 +0000 (+0000)
Subject: Add complete_read(), an EINTR-proof and partial-read-proof read,
X-Git-Tag: ppp-2.4.7~312
X-Git-Url: http://git.ozlabs.org/?p=ppp.git;a=commitdiff_plain;h=d524a1339c6016f60dcebdddc7536f510a558ada

Add complete_read(), an EINTR-proof and partial-read-proof read,
and use it for reading synchronization pipes.
---

diff --git a/pppd/main.c b/pppd/main.c
index 7b57a2a..6bb4b65 100644
--- a/pppd/main.c
+++ b/pppd/main.c
@@ -40,7 +40,7 @@
  * OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
  */
 
-#define RCSID	"$Id: main.c,v 1.124 2003/03/04 05:37:22 fcusack Exp $"
+#define RCSID	"$Id: main.c,v 1.125 2003/03/30 08:26:56 paulus Exp $"
 
 #include <stdio.h>
 #include <ctype.h>
@@ -822,7 +822,7 @@ detach()
 
     /* wait for parent to finish updating pid & lock files and die */
     close(pipefd[1]);
-    read(pipefd[0], numbuf, 1);
+    complete_read(pipefd[0], numbuf, 1);
     close(pipefd[0]);
 }
 
@@ -852,7 +852,7 @@ create_pidfile(pid)
     slprintf(pidfilename, sizeof(pidfilename), "%s%s.pid",
 	     _PATH_VARRUN, ifname);
     if ((pidfile = fopen(pidfilename, "w")) != NULL) {
-	fprintf(pidfile, "%d\n", getpid());
+	fprintf(pidfile, "%d\n", pid);
 	(void) fclose(pidfile);
     } else {
 	error("Failed to create pid file %s: %m", pidfilename);
@@ -872,7 +872,7 @@ create_linkpidfile(pid)
     slprintf(linkpidfile, sizeof(linkpidfile), "%sppp-%s.pid",
 	     _PATH_VARRUN, linkname);
     if ((pidfile = fopen(linkpidfile, "w")) != NULL) {
-	fprintf(pidfile, "%d\n", getpid());
+	fprintf(pidfile, "%d\n", pid);
 	if (ifname[0])
 	    fprintf(pidfile, "%s\n", ifname);
 	(void) fclose(pidfile);
@@ -1428,9 +1428,7 @@ safe_fork()
 	if (pid > 0) {
 		close(pipefd[1]);
 		/* this read() blocks until the close(pipefd[1]) below */
-		while (read(pipefd[0], buf, 1) < 0)
-		    if (errno != EINTR)
-			break;
+		complete_read(pipefd[0], buf, 1);
 		close(pipefd[0]);
 		return pid;
 	}
diff --git a/pppd/pppd.h b/pppd/pppd.h
index 60ca8b5..75b344f 100644
--- a/pppd/pppd.h
+++ b/pppd/pppd.h
@@ -39,7 +39,7 @@
  * AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING
  * OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
  *
- * $Id: pppd.h,v 1.80 2003/03/03 05:11:46 paulus Exp $
+ * $Id: pppd.h,v 1.81 2003/03/30 08:26:56 paulus Exp $
  */
 
 /*
@@ -511,6 +511,8 @@ void pr_log __P((void *, char *, ...));	/* printer fn, output to syslog */
 void end_pr_log __P((void));	/* finish up after using pr_log */
 void dump_packet __P((const char *, u_char *, int));
 				/* dump packet to debug log if interesting */
+ssize_t complete_read __P((int, void *, size_t));
+				/* read a complete buffer */
 
 /* Procedures exported from auth.c */
 void link_required __P((int));	  /* we are starting to use the link */
diff --git a/pppd/utils.c b/pppd/utils.c
index 8c70452..fb2c6aa 100644
--- a/pppd/utils.c
+++ b/pppd/utils.c
@@ -33,7 +33,7 @@
  * OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
  */
 
-#define RCSID	"$Id: utils.c,v 1.20 2002/12/04 23:03:33 paulus Exp $"
+#define RCSID	"$Id: utils.c,v 1.21 2003/03/30 08:26:56 paulus Exp $"
 
 #include <stdio.h>
 #include <ctype.h>
@@ -832,6 +832,32 @@ dump_packet(const char *tag, unsigned char *p, int len)
     dbglog("%s %P", tag, p, len);
 }
 
+/*
+ * complete_read - read a full `count' bytes from fd,
+ * unless end-of-file or an error other than EINTR is encountered.
+ */
+ssize_t
+complete_read(int fd, void *buf, size_t count)
+{
+	size_t done;
+	ssize_t nb;
+	char *ptr = buf;
+
+	for (done = 0; done < count; ) {
+		nb = read(fd, ptr, count - done);
+		if (nb < 0) {
+			if (errno == EINTR)
+				continue;
+			return -1;
+		}
+		if (nb == 0)
+			break;
+		done += nb;
+		ptr += nb;
+	}
+	return done;
+}
+
 /* Procedures for locking the serial device using a lock file. */
 #ifndef LOCK_DIR
 #ifdef __linux__