diff options
| -rw-r--r-- | README.md | 43 | ||||
| -rw-r--r-- | src/inflate.c (renamed from src/deflate.c) | 8 | ||||
| -rw-r--r-- | src/inflate.h (renamed from src/deflate.h) | 4 |
3 files changed, 30 insertions, 25 deletions
@@ -11,12 +11,17 @@ for speed. Right now, the implementation is naive, but usable. See below for the current status and TODOs. Be aware that this library has not been extensively tested yet. +Note: This library *inflates* (i.e., decompresses) data. The source files and +API are named as such, as is the corresponding function in the original zlib +implementation. However, as the algorithm is called *deflate*, the project is +named zlib-*deflate*-nostdlib even though it does not support compression. + ## Usage -Embed `deflate.c` and `deflate.h` into your project. You can rename `deflate.c` -to `deflate.cc` and/or compile it with g++ instead of gcc, if you like. Use -`deflate_zlib(input, input_len, output, output_len)` to decompress zlib data, -and `deflate(input, input_len, output, output_len)` to decompress deflate data +Embed `inflate.c` and `inflate.h` into your project. You can rename `inflate.c` +to `inflate.cc` and/or compile it with g++ instead of gcc, if you like. Use +`inflate_zlib(input, input_len, output, output_len)` to decompress zlib data, +and `inflate(input, input_len, output, output_len)` to decompress deflate data without zlib header. input and output must be `unsigned char *`, input\_len and output\_len are @@ -26,24 +31,24 @@ bytes written to `output`, or a negative value on error. Example for zlib decompression (RFC 1950): ``` -#include "deflate.h" +#include "inflate.h" -unsigned char deflate_input[] = { /* some compressed data, e.g.: */ +unsigned char inflate_input[] = { /* some compressed data, e.g.: */ 120, 156, 243, 72, 205, 201, 201, 215, 81, 8, 207, 47, 202, 73, 177, 87, 240, 64, 226, 41, 2, 0, 128, 125, 9, 17 }; -unsigned char deflate_output[128]; +unsigned char inflate_output[128]; // within some function { - int16_t out_bytes = deflate_zlib(deflate_input, sizeof(deflate_input), - deflate_output, sizeof(deflate_output)); + int16_t out_bytes = inflate_zlib(inflate_input, sizeof(inflate_input), + inflate_output, sizeof(inflate_output)); if (out_bytes < 0) { // error } else { - // success. deflate_output contains "Hello, World? Hello, World!" - // out_bytes contains the number of bytes written to deflate_output + // success. inflate_output contains "Hello, World? Hello, World!" + // out_bytes contains the number of bytes written to inflate_output } } @@ -52,24 +57,24 @@ unsigned char deflate_output[128]; Decompressing deflate (RFC 1951) data works as follows: ``` -#include "deflate.h" +#include "inflate.h" -unsigned char deflate_input[] = { /* some compressed data, e.g.: */ +unsigned char inflate_input[] = { /* some compressed data, e.g.: */ 243, 72, 205, 201, 201, 215, 81, 8, 207, 47, 202, 73, 177, 87, 240, 64, 226, 41, 2, 0 }; -unsigned char deflate_output[128]; +unsigned char inflate_output[128]; // within some function { - int16_t out_bytes = deflate(deflate_input, sizeof(deflate_input), - deflate_output, sizeof(deflate_output)); + int16_t out_bytes = inflate(inflate_input, sizeof(inflate_input), + inflate_output, sizeof(inflate_output)); if (out_bytes < 0) { // error } else { - // success. deflate_output contains "Hello, World? Hello, World!" - // out_bytes contains the number of bytes written to deflate_output + // success. inflate_output contains "Hello, World? Hello, World!" + // out_bytes contains the number of bytes written to inflate_output } } @@ -78,7 +83,7 @@ unsigned char deflate_output[128]; ## Compilation flags Compile with `-DDEFLATE_CHECKSUM` to enable verification of the zlib ADLER32 -checksum in `deflate_zlib`. +checksum in `inflate_zlib`. ## Compliance diff --git a/src/deflate.c b/src/inflate.c index 072cc97..8e83453 100644 --- a/src/deflate.c +++ b/src/inflate.c @@ -6,7 +6,7 @@ * SPDX-License-Identifier: BSD-2-Clause */ -#include "lib/deflate.h" +#include "lib/inflate.h" /* * The compressed (inflated) input data. @@ -370,7 +370,7 @@ static int8_t deflate_dynamic_huffman() deflate_lld_lengths + hlit, hdist); } -int16_t deflate(unsigned char *input_buf, uint16_t input_len, +int16_t inflate(unsigned char *input_buf, uint16_t input_len, unsigned char *output_buf, uint16_t output_len) { //uint8_t is_final = input_buf[0] & 0x01; @@ -405,7 +405,7 @@ int16_t deflate(unsigned char *input_buf, uint16_t input_len, return deflate_output_now - output_buf; } -int16_t deflate_zlib(unsigned char *input_buf, uint16_t input_len, +int16_t inflate_zlib(unsigned char *input_buf, uint16_t input_len, unsigned char *output_buf, uint16_t output_len) { if (input_len < 4) { @@ -427,7 +427,7 @@ int16_t deflate_zlib(unsigned char *input_buf, uint16_t input_len, } int16_t ret = - deflate(input_buf + 2, input_len - 2, output_buf, output_len); + inflate(input_buf + 2, input_len - 2, output_buf, output_len); #ifdef DEFLATE_CHECKSUM if (ret >= 0) { diff --git a/src/deflate.h b/src/inflate.h index 4ed28a0..575be4a 100644 --- a/src/deflate.h +++ b/src/inflate.h @@ -17,7 +17,7 @@ #define DEFLATE_ERR_FCHECK (-7) #define DEFLATE_ERR_NLEN (-8) -int16_t deflate(unsigned char *input_buf, uint16_t input_len, +int16_t inflate(unsigned char *input_buf, uint16_t input_len, unsigned char *output_buf, uint16_t output_len); -int16_t deflate_zlib(unsigned char *input_buf, uint16_t input_len, +int16_t inflate_zlib(unsigned char *input_buf, uint16_t input_len, unsigned char *output_buf, uint16_t output_len); |