[gmime: 1/5] Use /dev/urandom for test-cat.c

[Jeffrey Stedfast <fejj src gnome org>]

commit 627cf808d3ebe503456a2195185c14ad41c2a5fa
Author: Jeffrey Stedfast <jestedfa microsoft com>
Date:   Wed Apr 12 20:31:05 2017 -0400

    Use /dev/urandom for test-cat.c

 tests/test-cat.c |   80 +++++++++++++++++++++++++++++++++++++++++++++---------
 1 files changed, 67 insertions(+), 13 deletions(-)
---
diff --git a/tests/test-cat.c b/tests/test-cat.c
index 6a81c2f..26fc8df 100644
--- a/tests/test-cat.c
+++ b/tests/test-cat.c
@@ -47,6 +47,39 @@ extern int verbose;
 #define d(x)
 #define v(x) if (verbose > 3) x;
 
+static int randfd;
+
+static unsigned char
+randc (void)
+{
+       unsigned char c;
+       ssize_t n;
+       
+       do {
+               if ((n = read (randfd, &c, 1)) > 0)
+                   break;
+       } while (n == -1 && errno == EINTR);
+       
+       return c;
+}
+
+static float
+randf (void)
+{
+       size_t nread = 0;
+       unsigned int v;
+       ssize_t n;
+       
+       do {
+               if ((n = read (randfd, ((char *) &v) + nread, sizeof (v) - nread)) > 0) {
+                       if ((nread += n) == sizeof (v))
+                               break;
+               }
+       } while (n == -1 && errno == EINTR);
+       
+       return (v * 1.0) / UINT_MAX;
+}
+
 
 static GMimeStream *
 random_whole_stream (const char *datadir, char **filename)
@@ -58,7 +91,7 @@ random_whole_stream (const char *datadir, char **filename)
        int fd;
        
        /* read between 4k and 14k bytes */
-       size = 4096 + (size_t) (10240.0 * (rand () / (RAND_MAX + 1.0)));
+       size = 4096 + (size_t) (10240.0 * randf ());
        v(fprintf (stdout, "Generating %zu bytes of random data... ", size));
        v(fflush (stdout));
        
@@ -76,8 +109,12 @@ random_whole_stream (const char *datadir, char **filename)
        
        while (total < size) {
                buflen = size - total > sizeof (buf) ? sizeof (buf) : size - total;
-               for (i = 0; i < buflen; i++)
-                       buf[i] = (char) (255 * (rand () / (RAND_MAX + 1.0)));
+               
+               nwritten = 0;
+               do {
+                       if ((n = read (randfd, buf + nwritten, buflen - nwritten)) > 0)
+                               nwritten += n;
+               } while (nwritten < buflen);
                
                nwritten = 0;
                do {
@@ -328,7 +365,7 @@ test_cat_seek (GMimeStream *whole, struct _StreamPart *parts, int bounded)
        }
        
        /* calculate a random seek offset to compare at */
-       offset = (gint64) (len * (rand () / (RAND_MAX + 1.0)));
+       offset = (gint64) (len * randf ());
        
        if (g_mime_stream_seek (whole, offset, GMIME_STREAM_SEEK_SET) == -1) {
                ex = exception_new ("could not seek to %lld in original stream: %s",
@@ -385,9 +422,9 @@ test_cat_substream (GMimeStream *whole, struct _StreamPart *parts, int bounded)
        }
        
        /* calculate a random start/end offsets */
-       start = (gint64) (len * (rand () / (RAND_MAX + 1.0)));
-       if (rand () % 2)
-               end = start + (gint64) ((len - start) * (rand () / (RAND_MAX + 1.0)));
+       start = (gint64) (len * randf ());
+       if (randc () % 2)
+               end = start + (gint64) ((len - start) * randf ());
        else
                end = -1;
        
@@ -449,12 +486,13 @@ int main (int argc, char **argv)
        gint64 len;
        int fd, i;
        
-       srand (time (NULL));
-       
        g_mime_init ();
        
        testsuite_init (argc, argv);
        
+       if ((randfd = open ("/dev/urandom", O_RDONLY)) == -1)
+               return EXIT_FAILURE;
+       
        for (i = 1; i < argc; i++) {
                if (argv[i][0] != '-') {
                        datadir = argv[i];
@@ -466,16 +504,25 @@ int main (int argc, char **argv)
                if (stat (datadir, &st) == -1) {
                        if (errno == ENOENT) {
                                g_mkdir_with_parents (datadir, 0755);
-                               if (stat (datadir, &st) == -1)
+                               if (stat (datadir, &st) == -1) {
+                                       close (randfd);
+                                       
                                        return EXIT_FAILURE;
-                       } else
+                               }
+                       } else {
+                               close (randfd);
+                               
                                return EXIT_FAILURE;
+                       }
                }
                
                if (S_ISREG (st.st_mode)) {
                        /* test a particular input file */
-                       if ((fd = open (argv[i], O_RDONLY, 0)) == -1)
+                       if ((fd = open (argv[i], O_RDONLY, 0)) == -1) {
+                               close (randfd);
+                               
                                return EXIT_FAILURE;
+                       }
                        
                        filename = g_strdup (argv[i]);
                        whole = g_mime_stream_fs_new (fd);
@@ -483,6 +530,8 @@ int main (int argc, char **argv)
                        /* use path as test suite data dir */
                        whole = random_whole_stream (argv[i], &filename);
                } else {
+                       close (randfd);
+                       
                        return EXIT_FAILURE;
                }
        } else {
@@ -492,10 +541,14 @@ int main (int argc, char **argv)
        if ((wholelen = g_mime_stream_length (whole)) == -1) {
                fprintf (stderr, "Error: length of test stream unknown\n");
                g_object_unref (whole);
+               close (randfd);
+               
                return EXIT_FAILURE;
        } else if (wholelen == 64) {
                fprintf (stderr, "Error: length of test stream is unsuitable for testing\n");
                g_object_unref (whole);
+               close (randfd);
+               
                return EXIT_FAILURE;
        }
        
@@ -504,7 +557,7 @@ int main (int argc, char **argv)
        
        left = wholelen;
        while (left > 0) {
-               len = 1 + (gint64) (left * (rand () / (RAND_MAX + 1.0)));
+               len = 1 + (gint64) (left * randf ());
                n = g_new (struct _StreamPart, 1);
                sprintf (n->filename, "%s.%u", filename, part++);
                n->pstart = (gint64) 0; /* FIXME: we could make this a random offset */
@@ -550,6 +603,7 @@ int main (int argc, char **argv)
                unlink (filename);
        
        g_free (filename);
+       close (randfd);
        
        g_mime_shutdown ();