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-rw-r--r--lib/Support/Compressor.cpp179
1 files changed, 20 insertions, 159 deletions
diff --git a/lib/Support/Compressor.cpp b/lib/Support/Compressor.cpp
index e9bb781a2c..0a7253f790 100644
--- a/lib/Support/Compressor.cpp
+++ b/lib/Support/Compressor.cpp
@@ -26,12 +26,6 @@
#include <zlib.h>
#endif
-#ifndef HAVE_BZIP2
-# ifndef HAVE_ZLIB
-# warning No compression library is available!!
-# endif
-#endif
-
namespace {
inline int getdata(char*& buffer, unsigned& size,
@@ -45,19 +39,13 @@ inline int getdata(char*& buffer, unsigned& size,
}
//===----------------------------------------------------------------------===//
-//=== RLCOMP - very simple run length compression scheme
-//=== The code below transforms the input into blocks that are either
-//=== compressed or not. Each block starts with a header byte that provides
-//=== the length of the block. Values < 128 are uncompressed, values >128
-//=== are compressed. The value 128 is illegal. Currently, the algorithm is
-//=== not completed and is #if'd out.
+//=== NULLCOMP - a compression like set of routines that just copies data
+//=== without doing any compression. This is provided so that if the
+//=== configured environment doesn't have a compression library the
+//=== program can still work, albeit using more data/memory.
//===----------------------------------------------------------------------===//
-enum {
- MAX_RLCOMP_OUT = 32768
-};
-
-struct RLCOMP_stream {
+struct NULLCOMP_stream {
// User provided fields
char* next_in;
unsigned avail_in;
@@ -66,110 +54,19 @@ struct RLCOMP_stream {
// Information fields
uint64_t output_count; // Total count of output bytes
-
-#if 0
- // Algorithm fields
- unsigned block_len; // Length of current block
- unsigned compression; // State of compression 0=no, 1=yes, 2=indeterminate
- char buffer[128]; // compression buffer (not used for decompress)
- unsigned buflen; // bytes in compression buffer
- bool pending; // is data pending to be written
- char pending_data; // the pending data
- unsigned clen; // length of the compressed block
-#endif
};
-void RLCOMP_init(RLCOMP_stream* s) {
+void NULLCOMP_init(NULLCOMP_stream* s) {
s->output_count = 0;
-#if 0
- s->block_len = 0;
- s->compression = 2;
- s->buflen = 0;
- s->pending = false;
- s->pending_data = 0;
- s->clen = 0;
-#endif
}
-inline bool RLCOMP_getchar(RLCOMP_stream* s, unsigned& data) {
-#if 0
- if (s->avail_in) {
- data = *s->next_in++;
- s->avail_in--;
- return true;
- }
-#endif
- return false;
-}
-
-inline bool RLCOMP_putchar(RLCOMP_stream* s, unsigned data) {
-#if 0
- if (s->avail_out) {
- *s->next_out++ = data;
- s->avail_out--;
- s->output_count++;
- return true;
- } else {
- s->pending = true;
- s->pending_data = data;
- return false;
- }
-#else
- return false;
-#endif
-}
-
-bool RLCOMP_compress(RLCOMP_stream* s) {
- assert(s && "Invalid RLCOMP_stream");
+bool NULLCOMP_compress(NULLCOMP_stream* s) {
+ assert(s && "Invalid NULLCOMP_stream");
assert(s->next_in != 0);
assert(s->next_out != 0);
assert(s->avail_in >= 1);
assert(s->avail_out >= 1);
-#if 0
-
- // Handle pending data from the last time in
- if (s->pending) {
- RLCOMP_putchar(s,s->pending_data);
- s->pending = false;
- }
-
- unsigned c = 0;
- unsigned lastc = 0;
- // Handle the degenerate len=1 case
- if (!RLCOMP_getchar(s,lastc)) {
- RLCOMP_putchar(s,1);
- return RLCOMP_putchar(s,lastc);
- }
-
- while (RLCOMP_getchar(s,c)) {
- switch(s->compression) {
- case 0:
- if (lastc == c) {
- s->compression = 1;
- s->clen = 2 ;
- } else {
- if (!RLCOMP_putchar(s, c))
- return false;
- }
- break;
-
- case 1:
- if (lastc != c) {
- s->compression = 2;
- if (!RLCOMP_putchar(s, s->clen))
- return false;
- } else {
- s->clen++;
- }
- break;
-
- case 2:
- break;
- }
- lastc = c;
- }
-#endif
if (s->avail_out >= s->avail_in) {
::memcpy(s->next_out, s->next_in, s->avail_in);
s->output_count += s->avail_in;
@@ -187,49 +84,13 @@ bool RLCOMP_compress(RLCOMP_stream* s) {
}
}
-bool RLCOMP_decompress(RLCOMP_stream* s) {
- assert(s && "Invalid RLCOMP_stream");
+bool NULLCOMP_decompress(NULLCOMP_stream* s) {
+ assert(s && "Invalid NULLCOMP_stream");
assert(s->next_in != 0);
assert(s->next_out != 0);
assert(s->avail_in >= 1);
assert(s->avail_out >= 1);
-#if 0
- unsigned c = 0;
- while (RLCOMP_getchar(s,c)) {
- switch(s->compression) {
- case 0: // This is not a compressed block
- s->block_len--;
- if (!RLCOMP_putchar(s,c))
- return false;
- break;
-
- case 1: // This is a comperssed block
- while (s->block_len-- > 0)
- if (!RLCOMP_putchar(s,c))
- return false;
- break;
-
- case 2: // This is the length field
- if (c < 128) {
- s->compression = 0;
- s->block_len = c;
- } else {
- s->compression = 1;
- s->block_len = c - 128;
- }
- continue;
-
- default: // oops!
- throw std::string("Invalid compression state");
- }
- if (s->block_len <= 0)
- s->compression = 2;
- }
-
- if (s->repeat > 0)
- throw std::string("Invalid compression state");
-#endif
if (s->avail_out >= s->avail_in) {
::memcpy(s->next_out, s->next_in, s->avail_in);
s->output_count += s->avail_in;
@@ -247,7 +108,7 @@ bool RLCOMP_decompress(RLCOMP_stream* s) {
}
}
-void RLCOMP_end(RLCOMP_stream* strm) {
+void NULLCOMP_end(NULLCOMP_stream* strm) {
}
}
@@ -275,7 +136,7 @@ uint64_t Compressor::compress(char* in, unsigned size, OutputDataCallback* cb,
bzdata.avail_in = size;
bzdata.next_out = 0;
bzdata.avail_out = 0;
- switch ( BZ2_bzCompressInit(&bzdata, 9, 0, 0) ) {
+ switch ( BZ2_bzCompressInit(&bzdata, 9, 0, 100) ) {
case BZ_CONFIG_ERROR: throw std::string("bzip2 library mis-compiled");
case BZ_PARAM_ERROR: throw std::string("Compressor internal error");
case BZ_MEM_ERROR: throw std::string("Out of memory");
@@ -365,10 +226,10 @@ uint64_t Compressor::compress(char* in, unsigned size, OutputDataCallback* cb,
}
case COMP_TYPE_SIMPLE: {
- RLCOMP_stream sdata;
+ NULLCOMP_stream sdata;
sdata.next_in = in;
sdata.avail_in = size;
- RLCOMP_init(&sdata);
+ NULLCOMP_init(&sdata);
if (0 != getdata(sdata.next_out, sdata.avail_out,cb,context)) {
throw std::string("Can't allocate output buffer");
@@ -377,14 +238,14 @@ uint64_t Compressor::compress(char* in, unsigned size, OutputDataCallback* cb,
*(sdata.next_out++) = COMP_TYPE_SIMPLE;
sdata.avail_out--;
- while (!RLCOMP_compress(&sdata)) {
+ while (!NULLCOMP_compress(&sdata)) {
if (0 != getdata(sdata.next_out, sdata.avail_out,cb,context)) {
throw std::string("Can't allocate output buffer");
}
}
result = sdata.output_count + 1;
- RLCOMP_end(&sdata);
+ NULLCOMP_end(&sdata);
break;
}
default:
@@ -494,23 +355,23 @@ uint64_t Compressor::decompress(char *in, unsigned size,
}
case COMP_TYPE_SIMPLE: {
- RLCOMP_stream sdata;
+ NULLCOMP_stream sdata;
sdata.next_in = in;
sdata.avail_in = size - 1;
- RLCOMP_init(&sdata);
+ NULLCOMP_init(&sdata);
if (0 != getdata(sdata.next_out, sdata.avail_out,cb,context)) {
throw std::string("Can't allocate output buffer");
}
- while (!RLCOMP_decompress(&sdata)) {
+ while (!NULLCOMP_decompress(&sdata)) {
if (0 != getdata(sdata.next_out, sdata.avail_out,cb,context)) {
throw std::string("Can't allocate output buffer");
}
}
result = sdata.output_count;
- RLCOMP_end(&sdata);
+ NULLCOMP_end(&sdata);
break;
}
generated by cgit v1.2.3-18-g5258 (git 2.32.0) at 2025-04-30 12:00:06 +0000