From 80855ba8ca50b6efa69e9bfefb3cfc89dbabf850 Mon Sep 17 00:00:00 2001
From: Tom Lane <tgl@sss.pgh.pa.us>
Date: Mon, 20 Dec 2004 17:40:59 +0000
Subject: [PATCH] In pipe_read_line Windows code, loop to ensure we get a whole
line from the child process; fixes observed problems when the returned
version number is '8.0.0' rather than '8.0.0rc1'. Magnus Hagander
---
src/port/exec.c | 51 ++++++++++++++++++++++++++++++++-----------------
1 file changed, 34 insertions(+), 17 deletions(-)
diff --git a/src/port/exec.c b/src/port/exec.c
index 19ab92a0725..62a833cb852 100644
--- a/src/port/exec.c
+++ b/src/port/exec.c
@@ -9,7 +9,7 @@
*
*
* IDENTIFICATION
- * $PostgreSQL: pgsql/src/port/exec.c,v 1.33 2004/11/27 22:44:15 petere Exp $
+ * $PostgreSQL: pgsql/src/port/exec.c,v 1.34 2004/12/20 17:40:59 tgl Exp $
*
*-------------------------------------------------------------------------
*/
@@ -486,30 +486,45 @@ pipe_read_line(char *cmd, char *line, int maxsize)
&si,
&pi))
{
- DWORD bytesread = 0;
-
/* Successfully started the process */
+ char *lineptr;
ZeroMemory(line, maxsize);
- /* Let's see if we can read */
- if (WaitForSingleObject(childstdoutrddup, 10000) != WAIT_OBJECT_0)
+ /* Try to read at least one line from the pipe */
+ /* This may require more than one wait/read attempt */
+ for (lineptr = line; lineptr < line+maxsize-1; )
{
- /* Got timeout */
- CloseHandle(pi.hProcess);
- CloseHandle(pi.hThread);
- CloseHandle(childstdoutwr);
- CloseHandle(childstdoutrddup);
- return NULL;
+ DWORD bytesread = 0;
+
+ /* Let's see if we can read */
+ if (WaitForSingleObject(childstdoutrddup, 10000) != WAIT_OBJECT_0)
+ break; /* Timeout, but perhaps we got a line already */
+
+ if (!ReadFile(childstdoutrddup, lineptr, maxsize-(lineptr-line),
+ &bytesread, NULL))
+ break; /* Error, but perhaps we got a line already */
+
+ lineptr += strlen(lineptr);
+
+ if (!bytesread)
+ break; /* EOF */
+
+ if (strchr(line, '\n'))
+ break; /* One or more lines read */
}
- /* We try just once */
- if (ReadFile(childstdoutrddup, line, maxsize, &bytesread, NULL) &&
- bytesread > 0)
+ if (lineptr != line)
{
- /* So we read some data */
- int len = strlen(line);
- retval = line;
+ /* OK, we read some data */
+ int len;
+
+ /* If we got more than one line, cut off after the first \n */
+ lineptr = strchr(line,'\n');
+ if (lineptr)
+ *(lineptr+1) = '\0';
+
+ len = strlen(line);
/*
* If EOL is \r\n, convert to just \n. Because stdout is a
@@ -531,6 +546,8 @@ pipe_read_line(char *cmd, char *line, int maxsize)
*/
if (len == 0 || line[len - 1] != '\n')
strcat(line, "\n");
+
+ retval = line;
}
CloseHandle(pi.hProcess);