Merge branch 't/opus'

[paraslash.git] / wma_common.c

diff --git a/wma_common.c b/wma_common.c
index 3326cfff6148128f08ebc3b388ee82711a3c9ed5..b101d0a6e88e921d814e630113d59a263a657fd1 100644 (file)
--- a/wma_common.c
+++ b/wma_common.c
@@ -1,5 +1,5 @@
 /*
- * Copyright (C) 2009 Andre Noll <maan@systemlinux.org>
+ * Copyright (C) 2009-2013 Andre Noll <maan@systemlinux.org>
  *
  * Licensed under the GPL v2. For licencing details see COPYING.
  */
@@ -21,15 +21,27 @@
 #include "imdct.h"
 #include "wma.h"
 
-const char *search_pattern(const char *pattern, int pattern_len, const char *buf, int buf_size)
+/**
+ * Find the first occurrence of the given pattern.
+ *
+ * \param pattern The pattern to search for.
+ * \param pattern_len The length of the pattern in bytes.
+ * \param buf The buffer to search for the pattern.
+ * \param buf_size The number of bytes in \a buf.
+ *
+ * \return A pointer into \a buf or \p NULL if the pattern was not found.
+ */
+const char *search_pattern(const char *pattern, int pattern_len,
+               const char *buf, int buf_size)
 {
        const char *p, *end = buf + buf_size;
 
+       /* TODO: Use suffix arrays to speed up the search. */
        for (p = buf; p + pattern_len < end; p++) {
                if (memcmp(p, pattern, pattern_len))
                        continue;
                PARA_DEBUG_LOG("found %d byte pattern@%d\n",
-                       pattern_len, p - buf);
+                       pattern_len, (int)(p - buf));
                return p;
        }
        PARA_NOTICE_LOG("%d byte pattern not found\n", pattern_len);
@@ -46,11 +58,11 @@ static int find_audio_stream_info(const char *buf, int len)
 
        if (!p)
                return -E_WMA_NO_GUID;
-       PARA_DEBUG_LOG("found audio stream guid@%0zx\n", p - buf);
+       PARA_DEBUG_LOG("found audio stream guid@%0x\n", (int)(p - buf));
        return p - buf + 16;
 }
 
-static int read_header_len(char *buf, int len)
+static int read_header_len(const char *buf, int len)
 {
        uint16_t header_len;
 
@@ -71,10 +83,10 @@ static int read_header_len(char *buf, int len)
  * \return Negative on errors, zero if more data is needed in order to read the
  * full header, 1 on success.
  */
-int read_asf_header(char *buf, int loaded, struct asf_header_info *ahi)
+int read_asf_header(const char *buf, int loaded, struct asf_header_info *ahi)
 {
        int ret;
-       char *start;
+       const char *start;
 
        ahi->header_len = read_header_len(buf, loaded);
        if (ahi->header_len == 0) /* too short to read header len */
@@ -106,7 +118,7 @@ int read_asf_header(char *buf, int loaded, struct asf_header_info *ahi)
        return 1;
 }
 
-const uint8_t log2_tab[256] = {
+static const uint8_t log2_tab[256] = {
        0, 0, 1, 1, 2, 2, 2, 2, 3, 3, 3, 3, 3, 3, 3, 3, 4, 4, 4, 4, 4, 4, 4, 4,
        4, 4, 4, 4, 4, 4, 4, 4,
        5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5,
@@ -125,7 +137,14 @@ const uint8_t log2_tab[256] = {
        7, 7, 7, 7, 7, 7, 7, 7
 };
 
-int wma_log2(unsigned int v)
+/**
+ * Compute the base-2 logarithm.
+ *
+ * \param v The value to compute the logarithm of.
+ *
+ * \return An integer approximation of log2(v).
+ */
+__a_const int wma_log2(unsigned int v)
 {
        int n = 0;
        if (v & 0xffff0000) {