Issue 195: Code cleanups.

SVN-Revision: 3817

diff --git a/libarchive/archive_read_support_format_cab.c b/libarchive/archive_read_support_format_cab.c
index f8a00cd1ab6b8bdce5ef69d9b4eb3fa148103149..ff87dcef8adb4676073f24e95441850b897b84a4 100644 (file)
--- a/libarchive/archive_read_support_format_cab.c
+++ b/libarchive/archive_read_support_format_cab.c
@@ -392,10 +392,8 @@ archive_read_support_format_cab(struct archive *_a)
 }
 
 static int
-is_cab_magic(const void *h)
+find_cab_magic(const char *p)
 {
-       const unsigned char *p = h;
-
        switch (p[4]) {
        case 0:
                /*
@@ -405,8 +403,7 @@ is_cab_magic(const void *h)
                 * following four bytes which are reserved and must be set
                 * to zero.
                 */
-               if (p[0] == 'M' && p[1] == 'S' && p[2] == 'C' && p[3] == 'F' &&
-                   p[5] == 0 && p[6] == 0 && p[7] == 0)
+               if (memcmp(p, "MSCF\0\0\0\0", 8) == 0)
                        return 0;
                return 5;
        case 'F': return 1;
@@ -420,15 +417,14 @@ is_cab_magic(const void *h)
 static int
 archive_read_format_cab_bid(struct archive_read *a)
 {
-       const void *h;
        const char *p;
        ssize_t bytes_avail, offset, window;
 
-       if ((p = __archive_read_ahead(a, 4, NULL)) == NULL)
+       if ((p = __archive_read_ahead(a, 8, NULL)) == NULL)
                return (-1);
 
-       if (is_cab_magic(p) == 0)
-               return (32);
+       if (memcmp(p, "MSCF\0\0\0\0", 8) == 0)
+               return (64);
 
        /*
         * Attempt to handle self-extracting archives
@@ -439,7 +435,7 @@ archive_read_format_cab_bid(struct archive_read *a)
                offset = 0;
                window = 4096;
                while (offset < (1024 * 128)) {
-                       h = __archive_read_ahead(a, offset + window,
+                       const char *h = __archive_read_ahead(a, offset + window,
                            &bytes_avail);
                        if (h == NULL) {
                                /* Remaining bytes are less than window. */
@@ -448,14 +444,14 @@ archive_read_format_cab_bid(struct archive_read *a)
                                        return (0);
                                continue;
                        }
-                       p = (const char *)h + offset;
-                       while (p + 8 < (const char *)h + bytes_avail) {
+                       p = h + offset;
+                       while (p + 8 < h + bytes_avail) {
                                int next;
-                               if ((next = is_cab_magic(p)) == 0)
-                                       return (32);
+                               if ((next = find_cab_magic(p)) == 0)
+                                       return (64);
                                p += next;
                        }
-                       offset = p - (const char *)h;
+                       offset = p - h;
                }
        }
        return (0);
@@ -491,14 +487,13 @@ archive_read_format_cab_options(struct archive_read *a,
 static int
 cab_skip_sfx(struct archive_read *a)
 {
-       const void *h;
        const char *p, *q;
        size_t skip;
        ssize_t bytes, window;
 
        window = 4096;
        for (;;) {
-               h = __archive_read_ahead(a, window, &bytes);
+               const char *h = __archive_read_ahead(a, window, &bytes);
                if (h == NULL) {
                        /* Remaining size are less than window. */
                        window >>= 1;
@@ -519,14 +514,14 @@ cab_skip_sfx(struct archive_read *a)
                 */
                while (p + 8 < q) {
                        int next;
-                       if ((next = is_cab_magic(p)) == 0) {
-                               skip = p - (const char *)h;
+                       if ((next = find_cab_magic(p)) == 0) {
+                               skip = p - h;
                                __archive_read_consume(a, skip);
                                return (ARCHIVE_OK);
                        }
                        p += next;
                }
-               skip = p - (const char *)h;
+               skip = p - h;
                __archive_read_consume(a, skip);
        }
 }