[Buildroot] [PATCH] ext-toolchain-wrapper: fix paths if executable was resolved by PATH

[Patrick Ziegler]

If ext-toolchain-wrapper or any symbolic link to it was resolved by PATH,
the wrapper takes the working directory to calculate the relative paths.

Now '/proc/self/exe' is used to resolve the absolute path to the toolchain
directory if the wrapper was called neither with a relative nor an absolute
path.

Signed-off-by: Patrick Ziegler <patrick.ziegler at fh-kl.de>
---
 toolchain/toolchain-external/ext-toolchain-wrapper.c | 16 ++++++++++++++--
 1 file changed, 14 insertions(+), 2 deletions(-)

diff --git a/toolchain/toolchain-external/ext-toolchain-wrapper.c b/toolchain/toolchain-external/ext-toolchain-wrapper.c
index 9a2fc70..e71a90a 100644
--- a/toolchain/toolchain-external/ext-toolchain-wrapper.c
+++ b/toolchain/toolchain-external/ext-toolchain-wrapper.c
@@ -61,7 +61,7 @@ int main(int argc, char **argv)
 	char *relbasedir, *absbasedir;
 	char *progpath = argv[0];
 	char *basename;
-	int ret;
+	int ret, i, count = 0;
 
 	/* Calculate the relative paths */
 	basename = strrchr(progpath, '/');
@@ -77,7 +77,19 @@ int main(int argc, char **argv)
 		absbasedir = realpath(relbasedir, NULL);
 	} else {
 		basename = progpath;
-		absbasedir = realpath("../..", NULL);
+		absbasedir = malloc(PATH_MAX + 1);
+		ret = readlink("/proc/self/exe", absbasedir, PATH_MAX);
+		if (ret < 0) {
+			perror(__FILE__ ": readlink");
+			return 2;
+		}
+		for (i = ret; i > 0; i--) {
+			if ('/' == absbasedir[i]) {
+				absbasedir[i] = '\0';
+				if (3 == ++count)
+					break;
+			}
+		}
 	}
 	if (absbasedir == NULL) {
 		perror(__FILE__ ": realpath");
-- 
1.8.1.2


-- 
Dipl.-Inf. (FH) Patrick Ziegler

University Of Applied Sciences
Kaiserslautern

Amerikastrasse 1
D-66482 Zweibruecken
Germany

Phone:  +49 631 3724 5526
Mail:   patrick.ziegler at fh-kl.de
PGP KeyID 0xB4796B8C

http://www.fh-kl.de
http://www.fh-kl.de/fachbereiche/imst/iuk-knowhow.html