Mastering Algorithms with C Examples

/***************************************************************************** * * * sample.txt * * ========== * * * * Description: A copy of ex-1.c to use as a sample file to compress. * * * *****************************************************************************/ #include <ctype.h> #include <stdio.h> #include "compress.h" /***************************************************************************** * * * Define the size of data to compress. * * * *****************************************************************************/ #define DATSIZ 500000 /***************************************************************************** * * * --------------------------------- main --------------------------------- * * * *****************************************************************************/ int main(int argc, char **argv) { FILE *fp; unsigned char original[DATSIZ], *compressed, *restored; int csize, osize, rsize, c, i; /***************************************************************************** * * * Read some data to compress. * * * *****************************************************************************/ if ((fp = fopen("sample.txt", "r")) == NULL) return 1; i = 0; while ((c = getc(fp)) != EOF && i < DATSIZ) { original[i] = c; i++; } osize = i; fclose(fp); /***************************************************************************** * * * Compress the data using Huffman coding. * * * *****************************************************************************/ fprintf(stdout, "Testing Huffman coding\n"); fprintf(stdout, "Compressing..."); if ((csize = huffman_compress(original, &compressed, osize)) < 0) { fprintf(stdout, "\n"); return 1; } fprintf(stdout, "Done\n"); fprintf(stdout, "Uncompressing..."); if ((rsize = huffman_uncompress(compressed, &restored)) < 0) { fprintf(stdout, "\n"); free(compressed); return 1; } fprintf(stdout, "Done\n"); fprintf(stdout, "osize=%d, csize=%d, rsize=%d\n", osize, csize, rsize); if (rsize != osize) { fprintf(stdout, "Data was not properly restored\n"); free(compressed); free(restored); return 1; } else { for (i = 0; i < rsize; i++) { if (original[i] != restored[i]) { fprintf(stdout, "Data was not properly restored\n"); if (isgraph(original[i])) fprintf(stdout, "original[%d]=\"%c\"\n", i, original[i]); else fprintf(stdout, "original[%d]=0x%02x\n", i, original[i]); if (isgraph(restored[i])) fprintf(stdout, "restored[%d]=\"%c\"\n", i, restored[i]); else fprintf(stdout, "restored[%d]=0x%02x\n", i, restored[i]); free(compressed); free(restored); return 1; } } } fprintf(stdout, "Data was restored OK\n"); free(compressed); free(restored); /***************************************************************************** * * * Compress some data using LZ77. * * * *****************************************************************************/ fprintf(stdout, "Testing LZ77\n"); fprintf(stdout, "Compressing..."); if ((csize = lz77_compress(original, &compressed, osize)) < 0) return 1; fprintf(stdout, "Done\n"); fprintf(stdout, "Uncompressing..."); if ((rsize = lz77_uncompress(compressed, &restored)) < 0) { fprintf(stdout, "\n"); free(compressed); return 1; } fprintf(stdout, "Done\n"); fprintf(stdout, "osize=%d, csize=%d, rsize=%d\n", osize, csize, rsize); if (rsize != osize) { fprintf(stdout, "Data was not properly restored\n"); free(compressed); free(restored); return 1; } else { for (i = 0; i < rsize; i++) { if (original[i] != restored[i]) { fprintf(stdout, "Data was not properly restored\n"); if (isgraph(original[i])) fprintf(stdout, "original[%d]=\"%c\"\n", i, original[i]); else fprintf(stdout, "original[%d]=0x%02x\n", i, original[i]); if (isgraph(restored[i])) fprintf(stdout, "restored[%d]=\"%c\"\n", i, restored[i]); else fprintf(stdout, "restored[%d]=0x%02x\n", i, restored[i]); free(compressed); free(restored); return 1; } } } fprintf(stdout, "Data was restored OK\n"); free(compressed); free(restored); return 0; }