Fix for bug 2990360: relative path to working directory for gtm

Fix an issue with GTM path when its binary is called with a relative path
Ex: ./bin/gtm -D data-gtm

This was causing gtm to quit with a FATAL error because it was not able to
find gtm data repository correctly.

Patch written by Benny Wang

4 files changed, 119 insertions, 0 deletions

diff --git a/src/gtm/main/main.c b/src/gtm/main/main.c
index 80f35b32ae..9bfa9da475 100644
--- a/src/gtm/main/main.c
+++ b/src/gtm/main/main.c
@@ -26,6 +26,7 @@
 
 #include "gtm/gtm_c.h"
 #include "gtm/gtm.h"
+#include "gtm/path.h"
 #include "gtm/elog.h"
 #include "gtm/memutils.h"
 #include "gtm/gtm_list.h"
@@ -84,6 +85,7 @@ static void GTM_UnregisterPGXCNode(Port *myport, GTM_PGXCNodeId pgxc_node_id);
 static bool CreateOptsFile(int argc, char *argv[]);
 static void CreateDataDirLockFile(void);
 static void CreateLockFile(const char *filename, const char *refName);
+static void SetDataDir(void);
 static void ChangeToDataDir(void);
 static void checkDataDir(void);
 static void DeleteLockFile(const char *filename);
@@ -143,6 +145,7 @@ BaseInit()
 	MemoryContextInit();
 
 	checkDataDir();
+	SetDataDir();
 	ChangeToDataDir();
 	CreateDataDirLockFile();
 
@@ -1181,6 +1184,29 @@ retry:
 }
 
 /*
+ * Set data directory, but make sure it's an absolute path.  Use this,
+ * never set DataDir directly.
+ */
+void
+SetDataDir()
+{
+	char   *new;
+
+	/* If presented path is relative, convert to absolute */
+	new = make_absolute_path(GTMDataDir);
+	if (!new)
+		ereport(FATAL,
+			(errno,
+			 errmsg("failed to set the data directory \"%s\"",
+				GTMDataDir)));
+	
+	if (GTMDataDir)
+		free(GTMDataDir);
+
+	GTMDataDir = new;
+}
+
+/*
  * Change working directory to DataDir.  Most of the postmaster and backend
  * code assumes that we are in DataDir so it can use relative paths to access
  * stuff in and under the data directory.  For convenience during path
diff --git a/src/gtm/path/path.c b/src/gtm/path/path.c
index 11c62908ab..4a3298b3d7 100644
--- a/src/gtm/path/path.c
+++ b/src/gtm/path/path.c
@@ -20,6 +20,7 @@
 #include <sys/stat.h>
 #include <string.h>
 #include <stdio.h>
+#include <unistd.h>
 
 #include <gtm/path.h>
 
@@ -175,3 +176,64 @@ trim_trailing_separator(char *path)
 		for (p--; p > path && IS_DIR_SEP(*p); p--)
 			*p = '\0';
 }
+/*
+ * If the given pathname isn't already absolute, make it so, interpreting
+ * it relative to the current working directory.
+ *
+ * Also canonicalize the path. The result is always a malloc'd copy.
+ *
+ */
+char *
+make_absolute_path(const char *path)
+{
+	char	   *new;
+
+	/* Returning null for null input is convenient for some callers */
+	if (path == NULL)
+		return NULL;
+
+	if (!is_absolute_path(path))
+	{
+		char	   *buf;
+		size_t		buflen;
+
+		buflen = MAXPGPATH;
+		for (;;)
+		{
+			buf = malloc(buflen);
+			if (!buf)
+				return NULL;
+
+			if (getcwd(buf, buflen))
+				break;
+			else if (errno == ERANGE)
+			{
+				free(buf);
+				buflen *= 2;
+				continue;
+			}
+			else
+			{
+				free(buf);
+				return NULL;
+			}
+		}
+
+		new = malloc(strlen(buf) + strlen(path) + 2);
+		if (!new)
+		     return NULL;
+		sprintf(new, "%s/%s", buf, path);
+		free(buf);
+	}
+	else
+	{
+		new = strdup(path);
+		if (!new)
+		     return NULL;
+	}
+
+	/* Make sure punctuation is canonical, too */
+	canonicalize_path(new);
+
+	return new;
+}
diff --git a/src/gtm/proxy/proxy_main.c b/src/gtm/proxy/proxy_main.c
index f1e8553dd6..e7632e15d8 100644
--- a/src/gtm/proxy/proxy_main.c
+++ b/src/gtm/proxy/proxy_main.c
@@ -24,6 +24,7 @@
 #include <getopt.h>
 
 #include "gtm/gtm_c.h"
+#include "gtm/path.h"
 #include "gtm/gtm_proxy.h"
 #include "gtm/register.h"
 #include "gtm/elog.h"
@@ -112,6 +113,7 @@ static void GTMProxy_CommandPending(GTMProxy_ConnectionInfo *conninfo,
 static bool CreateOptsFile(int argc, char *argv[]);
 static void CreateDataDirLockFile(void);
 static void CreateLockFile(const char *filename, const char *refName);
+static void SetDataDir(void);
 static void ChangeToDataDir(void);
 static void checkDataDir(void);
 static void DeleteLockFile(const char *filename);
@@ -174,6 +176,7 @@ BaseInit()
 	MemoryContextInit();
 
 	checkDataDir();
+	SetDataDir();
 	ChangeToDataDir();
 	CreateDataDirLockFile();
 
@@ -2008,6 +2011,29 @@ retry:
 }
 
 /*
+ * Set data directory, but make sure it's an absolute path.  Use this,
+ * never set DataDir directly.
+ */
+void
+SetDataDir()
+{
+	char   *new;
+
+	/* If presented path is relative, convert to absolute */
+	new = make_absolute_path(GTMProxyDataDir);
+	if (!new)
+		ereport(FATAL,
+			(errno,
+			 errmsg("failed to set the data directory \"%s\"",
+				GTMProxyDataDir)));
+
+	if (GTMProxyDataDir)
+		free(GTMProxyDataDir);
+
+	GTMProxyDataDir = new;
+}
+
+/*
  * Change working directory to DataDir.  Most of the postmaster and backend
  * code assumes that we are in DataDir so it can use relative paths to access
  * stuff in and under the data directory.  For convenience during path
diff --git a/src/include/gtm/path.h b/src/include/gtm/path.h
index e95ca5e86b..cc07813ace 100644
--- a/src/include/gtm/path.h
+++ b/src/include/gtm/path.h
@@ -11,6 +11,11 @@
  *
  *-------------------------------------------------------------------------
  */
+#ifndef _PATH_H
+#define _PATH_H
+
 #include "gtm/gtm_c.h"
 
 extern void canonicalize_path(char *path);
+extern char *make_absolute_path(const char *path);
+#endif