[libdvdcss-devel] Replace cache-related magic numbers with proper definitions.

[Diego Biurrun]

libdvdcss | branch: master | Diego Biurrun <***@biurrun.de> | Tue Nov 4 12:51:06 2014 +0100| [6e7f5562752d19ece99b55576ef2cbfae4b1623e] | committer: Diego Biurrun

Replace cache-related magic numbers with proper definitions.

http://git.videolan.org/gitweb.cgi/libdvdcss.git/?a=commit;h=6e7f5562752d19ece99b55576ef2cbfae4b1623e

---

src/css.c | 3 ++-
src/css.h | 3 +++
src/libdvdcss.c | 40 +++++++++++++++++++++++++---------------
3 files changed, 30 insertions(+), 16 deletions(-)

diff --git a/src/css.c b/src/css.c
index b92d4c2..73a4906 100644
--- a/src/css.c
+++ b/src/css.c
@@ -213,7 +213,8 @@ int dvdcss_title ( dvdcss_t dvdcss, int i_block )
if( dvdcss->psz_cachefile[0] )
{
/* XXX: be careful, we use sprintf and not snprintf */
- sprintf( dvdcss->psz_block, "%.10x", i_block );
+ sprintf( dvdcss->psz_block, "%." CACHE_FILENAME_LENGTH_STRING "x",
+ i_block );
i_fd = open( dvdcss->psz_cachefile, O_RDONLY );
b_cache = 1;

diff --git a/src/css.h b/src/css.h
index 005a26c..573de3f 100644
--- a/src/css.h
+++ b/src/css.h
@@ -32,6 +32,9 @@
#include "common.h"
#include "dvdcss/dvdcss.h"

+#define CACHE_FILENAME_LENGTH 10
+#define CACHE_FILENAME_LENGTH_STRING "10"
+
#define KEY_SIZE 5

typedef uint8_t dvd_key_t[KEY_SIZE];
diff --git a/src/libdvdcss.c b/src/libdvdcss.c
index 2bfd98e..2fb09e2 100644
--- a/src/libdvdcss.c
+++ b/src/libdvdcss.c
@@ -136,6 +136,15 @@
#define mkdir(a, b) _mkdir(a)
#endif

+
+#define STRING_KEY_SIZE (KEY_SIZE * 2)
+#define INTERESTING_SECTOR 16
+#define DISC_TITLE_OFFSET 40
+#define DISC_TITLE_LENGTH 32
+#define MANUFACTURING_DATE_OFFSET 813
+#define MANUFACTURING_DATE_LENGTH 16
+
+
static void set_verbosity( dvdcss_t dvdcss )
{
const char *psz_verbose = getenv( "DVDCSS_VERBOSE" );
@@ -258,9 +267,10 @@ static char *set_cache_directory( dvdcss_t dvdcss )
{
return NULL;
}
- /* Check that we can add the ID directory and the block filename */
- else if( strlen( psz_cache ) + 1 + 32 + 1 + (KEY_SIZE * 2) + 10 + 1
- > PATH_MAX )
+ /* Check that there is enough space for the cache directory path and the
+ * block filename. The +1 are path separators and terminating null byte. */
+ else if( strlen( psz_cache ) + 1 + DISC_TITLE_LENGTH + 1 +
+ STRING_KEY_SIZE + CACHE_FILENAME_LENGTH + 1 > PATH_MAX )
{
print_error( dvdcss, "cache directory name is too long" );
return NULL;
@@ -403,7 +413,7 @@ LIBDVDCSS_EXPORT dvdcss_t dvdcss_open ( const char *psz_target )
if( psz_cache )
{
uint8_t p_sector[DVDCSS_BLOCK_SIZE];
- char psz_key[1 + KEY_SIZE * 2 + 1];
+ char psz_key[STRING_KEY_SIZE + 1];
char *psz_title;
uint8_t *psz_serial;
int i;
@@ -433,8 +443,8 @@ LIBDVDCSS_EXPORT dvdcss_t dvdcss_open ( const char *psz_target )
* - offset 40: disc title (32 uppercase chars)
* - offset 813: manufacturing date + serial no (16 digits) */

- i_ret = dvdcss->pf_seek( dvdcss, 16 );
- if( i_ret != 16 )
+ i_ret = dvdcss->pf_seek( dvdcss, INTERESTING_SECTOR );
+ if( i_ret != INTERESTING_SECTOR )
{
goto nocache;
}
@@ -446,10 +456,10 @@ LIBDVDCSS_EXPORT dvdcss_t dvdcss_open ( const char *psz_target )
}

/* Get the disc title */
- psz_title = (char *)p_sector + 40;
- psz_title[32] = '\0';
+ psz_title = (char *)p_sector + DISC_TITLE_OFFSET;
+ psz_title[DISC_TITLE_LENGTH] = '\0';

- for( i = 0 ; i < 32 ; i++ )
+ for( i = 0; i < DISC_TITLE_LENGTH; i++ )
{
if( psz_title[i] <= ' ' )
{
@@ -463,21 +473,21 @@ LIBDVDCSS_EXPORT dvdcss_t dvdcss_open ( const char *psz_target )
}

/* Get the date + serial */
- psz_serial = p_sector + 813;
- psz_serial[16] = '\0';
+ psz_serial = p_sector + MANUFACTURING_DATE_OFFSET;
+ psz_serial[MANUFACTURING_DATE_LENGTH] = '\0';

/* Check that all characters are digits, otherwise convert. */
- for( i = 0 ; i < 16 ; i++ )
+ for( i = 0 ; i < MANUFACTURING_DATE_LENGTH ; i++ )
{
if( psz_serial[i] < '0' || psz_serial[i] > '9' )
{
- char psz_tmp[16 + 1];
+ char psz_tmp[MANUFACTURING_DATE_LENGTH + 1];
sprintf( psz_tmp,
"%.2x%.2x%.2x%.2x%.2x%.2x%.2x%.2x",
psz_serial[0], psz_serial[1], psz_serial[2],
psz_serial[3], psz_serial[4], psz_serial[5],
psz_serial[6], psz_serial[7] );
- memcpy( psz_serial, psz_tmp, 16 );
+ memcpy( psz_serial, psz_tmp, MANUFACTURING_DATE_LENGTH );
break;
}
}
@@ -490,7 +500,7 @@ LIBDVDCSS_EXPORT dvdcss_t dvdcss_open ( const char *psz_target )
{
sprintf( &psz_key[i * 2], "%.2x", dvdcss->css.p_disc_key[i] );
}
- psz_key[KEY_SIZE * 2] = '\0';
+ psz_key[STRING_KEY_SIZE] = '\0';
}
else
{