Remove lzma_init() and other init functions from liblzma API.

Half of developers were already forgetting to use these
functions, which could have caused total breakage in some future
liblzma version or even now if --enable-small was used. Now
liblzma uses pthread_once() to do the initializations unless
it has been built with --disable-threads which make these
initializations thread-unsafe.

When --enable-small isn't used, liblzma currently gets needlessly
linked against libpthread (on systems that have it). While it is
stupid for now, liblzma will need threads in future anyway, so
this stupidity will be temporary only.

When --enable-small is used, different code CRC32 and CRC64 is
now used than without --enable-small. This made the resulting
binary slightly smaller, but the main reason was to clean it up
and to handle the lack of lzma_init_check().

The pkg-config file lzma.pc was renamed to liblzma.pc. I'm not
sure if it works correctly and portably for static linking
(Libs.private includes -pthread or other operating system
specific flags). Hopefully someone complains if it is bad.

lzma_rc_prices[] is now included as a precomputed array even
with --enable-small. It's just 128 bytes now that it uses uint8_t
instead of uint32_t. Smaller array seemed to be at least as fast
as the more bloated uint32_t array on x86; hopefully it's not bad
on other architectures.

1 files changed, 9 insertions, 16 deletions

diff --git a/src/liblzma/check/check.h b/src/liblzma/check/check.h
index 8f387799..73c6391d 100644
--- a/src/liblzma/check/check.h
+++ b/src/liblzma/check/check.h
@@ -57,46 +57,39 @@ typedef struct {
 } lzma_check_state;
 
 
+/// lzma_crc32_table[0] is needed by LZ encoder so we need to keep
+/// the array two-dimensional.
 #ifdef HAVE_SMALL
-extern uint32_t lzma_crc32_table[8][256];
-extern uint64_t lzma_crc64_table[4][256];
+extern uint32_t lzma_crc32_table[1][256];
 #else
 extern const uint32_t lzma_crc32_table[8][256];
 extern const uint64_t lzma_crc64_table[4][256];
 #endif
 
 
-/// \brief      Initializes *check depending on type
+/// \brief      Initialize *check depending on type
 ///
 /// \return     LZMA_OK on success. LZMA_UNSUPPORTED_CHECK if the type is not
 ///             supported by the current version or build of liblzma.
 ///             LZMA_PROG_ERROR if type > LZMA_CHECK_ID_MAX.
-///
 extern void lzma_check_init(lzma_check_state *check, lzma_check type);
 
-
-/// \brief      Updates *check
-///
+/// Update the check state
 extern void lzma_check_update(lzma_check_state *check, lzma_check type,
 		const uint8_t *buf, size_t size);
 
-
-/// \brief      Finishes *check
-///
+/// Finish the check calculation and store the result to check->buffer.u8.
 extern void lzma_check_finish(lzma_check_state *check, lzma_check type);
 
 
-extern void lzma_crc32_init(void);
-
-
-extern void lzma_crc64_init(void);
-
-
+/// Prepare SHA-256 state for new input.
 extern void lzma_sha256_init(lzma_check_state *check);
 
+/// Update the SHA-256 hash state
 extern void lzma_sha256_update(
 		const uint8_t *buf, size_t size, lzma_check_state *check);
 
+/// Finish the SHA-256 calculation and store the result to check->buffer.u8.
 extern void lzma_sha256_finish(lzma_check_state *check);
 
 #endif