scanelg: add --ldcache=<arg> option to ease testing

Signed-off-by: Sergei Trofimovich <slyfox@gentoo.org>

4 files changed, 16 insertions, 1 deletions

diff --git a/man/scanelf.docbook b/man/scanelf.docbook
index d9032a9..22503b2 100644
--- a/man/scanelf.docbook
+++ b/man/scanelf.docbook
@@ -214,6 +214,13 @@
     listing ELFs.
    </para></listitem>
   </varlistentry>
+  <varlistentry>
+   <term><option>--ldcache</option> <replaceable>PATH</replaceable></term>
+   <listitem><para>
+    Use specified path instead of /etc/ld.so.cache. Generally paired with
+    options like -L or -n.
+   </para></listitem>
+  </varlistentry>
  </variablelist>
 </refsect1>
 
diff --git a/paxldso.c b/paxldso.c
index 0cb7b01..2d8ddea 100644
--- a/paxldso.c
+++ b/paxldso.c
@@ -156,7 +156,7 @@ char *ldso_cache_lookup_lib(elfobj *elf, const char *fname)
 
 	if (ldcache == NULL) {
 		int fd;
-		const char *cachefile = root_rel_path("/etc/ld.so.cache");
+		const char *cachefile = root_rel_path(ldcache_path);
 		struct stat st;
 
 		if (fstatat(root_fd, cachefile, &st, 0))
@@ -369,3 +369,5 @@ void paxldso_cleanup(void)
 	ldso_config_cleanup();
 }
 #endif
+
+const char * ldcache_path = "/etc/ld.so.cache";
diff --git a/paxldso.h b/paxldso.h
index 16cbbac..fb7d938 100644
--- a/paxldso.h
+++ b/paxldso.h
@@ -66,4 +66,7 @@ extern void paxldso_cleanup(void);
 # define paxldso_cleanup()
 #endif
 
+/* Path to ld.so.cache. Usually overridden for tests. */
+extern const char * ldcache_path;
+
 #endif
diff --git a/scanelf.c b/scanelf.c
index c2bda35..50497b2 100644
--- a/scanelf.c
+++ b/scanelf.c
@@ -1832,6 +1832,7 @@ static void scanelf_envpath(void)
 static struct option const long_opts[] = {
 	{"path",      no_argument, NULL, 'p'},
 	{"ldpath",    no_argument, NULL, 'l'},
+	{"ldcache",    a_argument, NULL, 130},
 	{"use-ldpath",no_argument, NULL, 129},
 	{"root",       a_argument, NULL, 128},
 	{"recursive", no_argument, NULL, 'R'},
@@ -1877,6 +1878,7 @@ static struct option const long_opts[] = {
 static const char * const opts_help[] = {
 	"Scan all directories in PATH environment",
 	"Scan all directories in /etc/ld.so.conf",
+	"Use alternate ld.so.cache specified in <arg>",
 	"Use ld.so.conf to show full path (use with -r/-n)",
 	"Root directory (use with -l or -p)",
 	"Scan directories recursively",
@@ -2120,6 +2122,7 @@ static int parseargs(int argc, char *argv[])
 				err("Could not open root: %s", optarg);
 			break;
 		case 129: load_cache_config = use_ldpath = 1; break;
+		case 130: ldcache_path = optarg; break;
 		case ':':
 			err("Option '%c' is missing parameter", optopt);
 		case '?':