[PATCH] ldd: take LD_LIBRARY_PATH into account

[Carmelo AMOROSO]

Extend the environment variables adding the LD_LIBRARY_PATH
if actually passed when doing shared library tracings through
the ld.so trace capability.

Signed-off-by: Carmelo Amoroso <carmelo.amoroso at st.com>
---
 utils/ldd.c |   41 ++++++++++++++++++++++++++++++++++++++++-
 1 files changed, 40 insertions(+), 1 deletions(-)

diff --git a/utils/ldd.c b/utils/ldd.c
index 6d08efd..00e46ca 100644
--- a/utils/ldd.c
+++ b/utils/ldd.c
@@ -127,6 +127,10 @@
 #define ELFDATAM	ELFDATA2MSB
 #endif
 
+#include <stdint.h>
+
+#define ARRAY_SIZE(v)	(sizeof(v) / sizeof(*v))
+
 struct library {
 	char *name;
 	int resolved;
@@ -699,15 +703,50 @@ foo:
 				NULL
 			};
 
+			/* The 'extended' environment inclusing the LD_LIBRARY_PATH */
+			static char *ext_environment[ARRAY_SIZE(environment) + 1];
+
+			char **envp = (char **) environment;
+
+			char * lib_path = getenv("LD_LIBRARY_PATH");
+
+			if (lib_path) {
+				/*
+				 * If the LD_LIBRARY_PATH is set, it needs to include it
+				 * into the environment for the new process to be spawned
+				 */
+				uint8_t k;
+				uint8_t size = ARRAY_SIZE(environment);
+
+				/* Copy the N-1 environment's entries */
+				for(k = 0; k < size - 1; k++)
+					ext_environment[k] = (char *) environment[k];
+
+				/* Make room for LD_LIBRARY_PATH */
+				ext_environment[k] = (char *) malloc(strlen("LD_LIBRARY_PATH=") + strlen(lib_path) + 1);
+				strcpy(ext_environment[k], "LD_LIBRARY_PATH=");
+				strcat(ext_environment[k], lib_path);
+
+				/* ext_environment[size] is already NULL */
+
+				/* Use the extended environment */
+				envp = ext_environment;
+			}
+
 			if ((pid = vfork()) == 0) {
 				/* Cool, it looks like we should be able to actually
 				 * run this puppy.  Do so now... */
-				execle(filename, filename, NULL, environment);
+				execle(filename, filename, NULL, envp);
 				_exit(0xdead);
 			}
 
 			/* Wait till it returns */
 			waitpid(pid, &status, 0);
+
+			/* Do not leak */
+			if (lib_path)
+				free(ext_environment[ARRAY_SIZE(ext_environment) - 2]);
+
 			if (WIFEXITED(status) && WEXITSTATUS(status) == 0) {
 				return 1;
 			}
-- 
1.7.4.4