Faster fuzz test: teach the fuzz test programs to handle directories

Instead of invoking the fuzz test programs once for every corpora
file, we invoke them once for each directory of corpora files.  This
dramatically reduces the number of program invokations, as well as the
time 90-test_fuzz.t takes to complete.

fuzz/test-corpus.c was enhanced to handle directories as well as
regular files.

Reviewed-by: Bernd Edlinger <bernd.edlinger@hotmail.de>
(Merged from https://github.com/openssl/openssl/pull/5788)

1 files changed, 70 insertions, 15 deletions

diff --git a/fuzz/test-corpus.c b/fuzz/test-corpus.c
index c553697d6c..7eeac4ca90 100644
--- a/fuzz/test-corpus.c
+++ b/fuzz/test-corpus.c
@@ -16,31 +16,86 @@
 
 #include <stdio.h>
 #include <stdlib.h>
+#include <string.h>
 #include <sys/stat.h>
 #include <openssl/crypto.h>
 #include "fuzzer.h"
+#include "internal/o_dir.h"
 
-int main(int argc, char **argv) {
-    int n;
+#if defined(_WIN32) && defined(_MAX_PATH)
+# define PATH_MAX _MAX_PATH
+#endif
 
-    FuzzerInitialize(&argc, &argv);
+#ifndef PATH_MAX
+# define PATH_MAX 4096
+#endif
 
-    for (n = 1; n < argc; ++n) {
-        struct stat st;
-        FILE *f;
-        unsigned char *buf;
-        size_t s;
-
-        stat(argv[n], &st);
-        f = fopen(argv[n], "rb");
-        if (f == NULL)
-            continue;
-        buf = malloc(st.st_size);
+# if !defined(S_ISREG)
+#   define S_ISREG(m) ((m) & S_IFREG)
+# endif
+
+static void testfile(const char *pathname)
+{
+    struct stat st;
+    FILE *f;
+    unsigned char *buf;
+    size_t s;
+
+    if (stat(pathname, &st) < 0 || !S_ISREG(st.st_mode))
+        return;
+    printf("# %s\n", pathname);
+    fflush(stdout);
+    f = fopen(pathname, "rb");
+    if (f == NULL)
+        return;
+    buf = malloc(st.st_size);
+    if (buf != NULL) {
         s = fread(buf, 1, st.st_size, f);
         OPENSSL_assert(s == (size_t)st.st_size);
         FuzzerTestOneInput(buf, s);
         free(buf);
-        fclose(f);
+    }
+    fclose(f);
+}
+
+int main(int argc, char **argv) {
+    int n;
+
+    FuzzerInitialize(&argc, &argv);
+
+    for (n = 1; n < argc; ++n) {
+        size_t dirname_len = strlen(argv[n]);
+        const char *filename = NULL;
+        char *pathname = NULL;
+        OPENSSL_DIR_CTX *ctx = NULL;
+        int wasdir = 0;
+
+        /*
+         * We start with trying to read the given path as a directory.
+         */
+        while ((filename = OPENSSL_DIR_read(&ctx, argv[n])) != NULL) {
+            wasdir = 1;
+            if (pathname == NULL) {
+                pathname = malloc(PATH_MAX);
+                if (pathname == NULL)
+                    break;
+                strcpy(pathname, argv[n]);
+#ifdef __VMS
+                if (strchr(":<]", pathname[dirname_len - 1]) == NULL)
+#endif
+                    pathname[dirname_len++] = '/';
+                pathname[dirname_len] = '\0';
+            }
+            strcpy(pathname + dirname_len, filename);
+            testfile(pathname);
+        }
+        OPENSSL_DIR_end(&ctx);
+
+        /* If it wasn't a directory, treat it as a file instead */
+        if (!wasdir)
+            testfile(argv[n]);
+
+        free(pathname);
     }
     return 0;
 }