X-Git-Url: https://git.llucax.com/z.facultad/75.06/jacu.git/blobdiff_plain/79645739ff07715a03ede8547baffee9cc22e581..d53cc94464bba53e0be1297ca0cc746901ec113b:/src/statichuff/statichuff.c?ds=sidebyside diff --git a/src/statichuff/statichuff.c b/src/statichuff/statichuff.c index db164d2..f339ef0 100644 --- a/src/statichuff/statichuff.c +++ b/src/statichuff/statichuff.c @@ -1,8 +1,10 @@ #include "statichuff.h" #include +#include -void putbit(char bit, char restart, char flush, FILE *fp) +/** Coloca un bit en un buffer statico */ +void putbit(char bit, char restart, char flush, VFILE *fp) { static unsigned long int bits_buffer = 0; static unsigned char bits_used = 0; @@ -10,7 +12,7 @@ void putbit(char bit, char restart, char flush, FILE *fp) /* me obligan a emitir el output */ if ((flush == 1) && (bits_used > 0)) { bits_buffer = bits_buffer << ((sizeof(unsigned long int)*8) - bits_used); - fwrite(&bits_buffer,sizeof(unsigned long int),1,fp); + vfwrite(&bits_buffer,sizeof(unsigned long int),1,fp); bits_buffer = 0; bits_used = 0; return; @@ -27,13 +29,14 @@ void putbit(char bit, char restart, char flush, FILE *fp) /* lleno el buffer, escribo */ if (bits_used == 32) { - fwrite(&bits_buffer,sizeof(unsigned long int),1,fp); + vfwrite(&bits_buffer,sizeof(unsigned long int),1,fp); bits_buffer = 0; bits_used = 0; } return; } +/** Realiza la copia de los datos de un nodo de huffman a otro */ void shuff_cpynode(SHUFFNODE *node1, SHUFFNODE *node2) { node1->symbol = node2->symbol; @@ -42,6 +45,7 @@ void shuff_cpynode(SHUFFNODE *node1, SHUFFNODE *node2) node1->rchild = node2->rchild; } +/** Realiza una comparacion de dos nodos de huffman */ int shuff_compnode(const void *node1, const void *node2) { if (((SHUFFNODE*)node1)->freq < ((SHUFFNODE*)node2)->freq) return 1; @@ -49,21 +53,64 @@ int shuff_compnode(const void *node1, const void *node2) return 0; } +/** Destruye un arbol de huffman recursivamente */ +void shuff_destroy_tree(SHUFFNODE *node) { + /* Si llegue a una hoja, destruyo y vuelvo */ + if (node->symbol < 256) { + free(node); + return; + } + else { + /* Desciendo por izq, luego por derecha y luego libero */ + shuff_destroy_tree(node->lchild); + shuff_destroy_tree(node->rchild); + free(node); + return; + } +} + +/** Reescala las frecuencias de huffman a la mitad */ int shuff_rescalefreq(t_freq *freqtable) { int i; t_freq totalfreq = 0; /* Divido por la mitad las frecuencias, asegurando de no perder */ - /* frequencias en 1, por ello le sumo 1 antes de partir */ for (i = 0; i < 256; i++) { - freqtable[i] = (freqtable[i] << 2) | 1; + freqtable[i] = (freqtable[i] >> 2) | 1; totalfreq += freqtable[i]; } return totalfreq; } +/** Escanea las frecuencias de un chunk de datos */ +int shuff_scanfreq_chunk(HUFF_STATE *chunkshuff, char* chunk, int chunksize) +{ + /* Locals */ + int i = 0; + unsigned char symbol = 0; + + /* Contamos las frecuencias del chunk a menos que se use un canonico */ + if (!chunkshuff->canonic) { + for (i = 0; i < chunksize; ++i) { + symbol = chunk[i]; + chunkshuff->freqtable[symbol] += 1; + chunkshuff->sumfreq += 1; + + /* Si llegue al tope de freq acumulada, halve em */ + if (chunkshuff->sumfreq == 14930352) + chunkshuff->sumfreq = shuff_rescalefreq(chunkshuff->freqtable); + } + } + + /* Dumpeamos el chunk en el temporal homero */ + fwrite(chunk,chunksize,1,chunkshuff->coderfp); + + return 1; +} + +/** Escanea las frecuencias de un archivo y genera el modelo */ int shuff_scanfreq(char *inputfile, t_freq *freqtable) { /* Locals */ @@ -75,7 +122,7 @@ int shuff_scanfreq(char *inputfile, t_freq *freqtable) for (i = 0; i < 256; ++i) freqtable[i] = 0; /* Abrimos el file */ - if ((fp = fopen(inputfile,"rb")) == NULL) return 0; + if ((fp = fopen(inputfile,"r")) == NULL) return 0; while (!feof(fp)) { /* Contamos las frecuencias */ symbol = fgetc(fp); @@ -90,9 +137,10 @@ int shuff_scanfreq(char *inputfile, t_freq *freqtable) } fclose(fp); - return 1; + return 1; } +/** Genera un input list que sera utilizada para generar el arbol */ SHUFFNODE *shuff_buildlist(t_freq *freqtable, int *nonzerofreqs) { int i,j = 0,nonzero = 0; @@ -116,14 +164,21 @@ SHUFFNODE *shuff_buildlist(t_freq *freqtable, int *nonzerofreqs) return inputlist; } -SHUFFNODE *shuff_buildtree(SHUFFNODE *list, int listcount) +/** Genera el arbol de huffman en base a la tabla de frecuencias */ +SHUFFNODE *shuff_buildtree(t_freq *ftable) { - SHUFFNODE *lastsymbol = list+(listcount-1); - SHUFFNODE *node1,*node2; + SHUFFNODE *lastsymbol; + SHUFFNODE *node1,*node2,*root; + SHUFFNODE *inputlist; + int freqcount = 0; - while (lastsymbol > list) { + /* Genero la input list en base a la cual genera el arbol */ + inputlist = shuff_buildlist(ftable, &freqcount); + lastsymbol = inputlist+(freqcount-1); + + while (lastsymbol > inputlist) { /* Ordeno la lista por frecuencia descendente */ - qsort(list,listcount,sizeof(SHUFFNODE),shuff_compnode); + qsort(inputlist,freqcount,sizeof(SHUFFNODE),shuff_compnode); /* Tomo los ultimos dos elementos, generando dos nodos del arbol */ node1 = (SHUFFNODE*)malloc(sizeof(SHUFFNODE)); node2 = (SHUFFNODE*)malloc(sizeof(SHUFFNODE)); @@ -135,13 +190,21 @@ SHUFFNODE *shuff_buildtree(SHUFFNODE *list, int listcount) lastsymbol->freq = node1->freq + node2->freq; lastsymbol->lchild = node1; lastsymbol->rchild = node2; - --listcount; + --freqcount; } - + + /* Copio la raiz para poder liberar la lista sin perderla */ + root = (SHUFFNODE*)malloc(sizeof(SHUFFNODE)); + shuff_cpynode(root,lastsymbol); + + /* Free up mem */ + free(inputlist); + /* Devuelvo el puntero a la raiz del arbol de huffman */ - return lastsymbol; + return root; } +/** Imprime los codigos prefijos generados para los symbolos */ void shuff_printcodes(SHUFFCODE *codetable,t_freq *freqtable) { int i,j; @@ -151,7 +214,7 @@ void shuff_printcodes(SHUFFCODE *codetable,t_freq *freqtable) for (i = 0; i < 256; ++i) { if (codetable[i].codelength > 0) { auxcode = codetable[i].code; - printf("Symbol:%i Freq: %li Code:",i,freqtable[i]); + printf("Symbol:%i Freq: %lu Code:",i,freqtable[i]); for (j = codetable[i].codelength-1; j >= 0; --j) { auxcode = codetable[i].code; auxcode = auxcode >> j; @@ -163,6 +226,7 @@ void shuff_printcodes(SHUFFCODE *codetable,t_freq *freqtable) } } +/** Inicializa la tabla de codigos prefijos */ void shuff_zerocodes(SHUFFCODE *table) { int i; @@ -174,6 +238,7 @@ void shuff_zerocodes(SHUFFCODE *table) } } +/** Genera la tabla de codigos prefijos en base al árbol de huffman */ void shuff_buildcodes(SHUFFCODE *table, SHUFFNODE *node, int level, int code) { if (node->symbol < 256) { @@ -189,25 +254,29 @@ void shuff_buildcodes(SHUFFCODE *table, SHUFFNODE *node, int level, int code) } } - - -int shuff_encode_symbols(t_freq *ftable, SHUFFCODE *ctable, char* inputfile, char *outputfile) { - - FILE *fpsource,*fpdest; +/** Realiza la compresion / encoding efectivo de un archivo */ +int shuff_encode_symbols(HUFF_STATE *shuff, SHUFFCODE *ctable) +{ + FILE *fpsource; + VFILE *fpdest; int symbol,i; unsigned long int sourcesize; char bit; SHUFFCODE symbolcode; - /* Abrimos el file */ - if ((fpsource = fopen(inputfile,"rb")) == NULL) return 0; - if ((fpdest = fopen(outputfile,"wb")) == NULL) return 0; + /* Abrimos el source y el destino */ + if (shuff->coderfp != NULL) { + fclose(shuff->coderfp); /* close bychunk temp file */ + shuff->coderfp = NULL; + } + if ((fpsource = fopen(shuff->sourcefile,"r")) == NULL) return 0; + if ((fpdest = vfopen(shuff->targetfile,"w",shuff->volsize)) == NULL) return 0; /* Guardamos el size el archivo original e inputlist como header */ fseek(fpsource,0,SEEK_END); sourcesize = ftell(fpsource); - fwrite(&sourcesize,sizeof(unsigned long int),1,fpdest); - fwrite(ftable,sizeof(t_freq),256,fpdest); + vfwrite(&sourcesize,sizeof(unsigned long int),1,fpdest); + vfwrite(shuff->freqtable,sizeof(t_freq),256,fpdest); /* Encodeo */ fseek(fpsource,0,SEEK_SET); @@ -227,42 +296,38 @@ int shuff_encode_symbols(t_freq *ftable, SHUFFCODE *ctable, char* inputfile, cha /* Hacemos un flush de lo que haya quedado en el buffer de salida */ putbit(0,0,1,fpdest); fclose(fpsource); - fclose(fpdest); + vfclose(fpdest); return 1; } -int shuff_encode_file(char *inputfile, char *outputfile) +/** Prepara las estructuras de datos necesarias para una compresion */ +int shuff_encode_file(HUFF_STATE *shuff) { - /* Locals */ - t_freq *freqtable = (t_freq*)malloc(sizeof(t_freq)*256); - SHUFFNODE *inputlist; - SHUFFNODE *codetree; + /* Locals */ SHUFFCODE *codetable = (SHUFFCODE*)malloc(sizeof(SHUFFCODE)*256); - int freqcount = 0; - /* Armamos la tabla de frecuencias */ - if (!shuff_scanfreq(inputfile,freqtable)) return 0; + /* Veo si debo armar una freqtable o si esta preloaded */ + if ((!shuff->canonic) && (!shuff->bychunk)) + if (!shuff_scanfreq(shuff->sourcefile,shuff->freqtable)) return 0; - /* Armo el input list y genero el arbol de huffman */ - inputlist = shuff_buildlist(freqtable, &freqcount); - codetree = shuff_buildtree(inputlist,freqcount); + /* Genero el arbol de huffman */ + shuff->codetree = shuff_buildtree(shuff->freqtable); /* Armo la tabla de codigos prefijos para el encoder */ shuff_zerocodes(codetable); - shuff_buildcodes(codetable,codetree,0,0); - /*shuff_printcodes(codetable,freqtable);*/ + shuff_buildcodes(codetable,shuff->codetree,0,0); + /*shuff_printcodes(codetable,shuff->freqtable);*/ /* Encodeo byte per byte */ - shuff_encode_symbols(freqtable,codetable,inputfile,outputfile); + shuff_encode_symbols(shuff,codetable); - /* Free up memory baby yeah */ - free(freqtable); - free(inputlist); + /* Free up memory baby yeah */ free(codetable); return 1; } +/** Decodifica una serie de bits en un symbolo y lo devuelve */ SHUFFNODE *shuff_decode_symbols(SHUFFNODE *entrynode, unsigned long int buffer, int *bitsleft, unsigned short int *symbol) { @@ -280,95 +345,220 @@ SHUFFNODE *shuff_decode_symbols(SHUFFNODE *entrynode, unsigned long int buffer, else return shuff_decode_symbols(entrynode->rchild,buffer,bitsleft,symbol); } -int shuff_decode_file(char *inputfile, char *outputfile) +/** Decodifica chunksize symbolos y los devuelve en un chunk de datos */ +int shuff_decode_chunk(HUFF_STATE *shuff, char *chunk, int chunksize, unsigned long int *decodedbytes) { - SHUFFNODE *inputlist; - SHUFFNODE *codetree,*currnode; - t_freq *ftable = (t_freq*)malloc(sizeof(t_freq)*256); - unsigned long int bytesleft,codebuffer; - FILE *fpsource; + SHUFFNODE *currnode = shuff->codetree; + unsigned short int decoded_symbol; + *decodedbytes = 0; + + while (!vfeof(shuff->decoderfp) && (shuff->bytesleft > 0) && (*decodedbytes < chunksize)) { + + /* Leo un buffer de 32 bits si es que quedo vacio el anterior */ + if (shuff->bitsleft == 0) { + if (vfread(&(shuff->codebuffer),sizeof(unsigned long int),1,shuff->decoderfp) != 1) continue; + shuff->bitsleft = sizeof(unsigned long int) * 8; + } + + /* Proceso el buffer sacando simbolos till se me agote el buffer, file o chunk */ + while ((shuff->bitsleft > 0) && (shuff->bytesleft > 0) && (*decodedbytes < chunksize)) { + currnode = shuff_decode_symbols(currnode,shuff->codebuffer,&(shuff->bitsleft),&decoded_symbol); + /* Si obtuve un symbolo valido lo emito*/ + if (decoded_symbol != 256) { + chunk[(*decodedbytes)++] = decoded_symbol; + currnode = shuff->codetree; + --(shuff->bytesleft); + } + } + } + + if (shuff->bytesleft == 0) return 0; + else return 1; +} + +/** Realiza la descompresión de un archivo comprimido */ +int shuff_decode_file(HUFF_STATE *shuff) +{ + SHUFFNODE *currnode; + unsigned long int codebuffer; FILE *fpdest; unsigned short int decoded_symbol; - int bitsleft,freqcount = 0; - - /* Levanto cuantos bytes decodeo y la freq table */ - if ((fpsource = fopen(inputfile,"rb")) == NULL) return 0; - if ((fpdest = fopen(outputfile,"wb")) == NULL) return 0; - fread(&bytesleft,sizeof(unsigned long int),1,fpsource); - fread(ftable,sizeof(unsigned long int),256,fpsource); - inputlist = shuff_buildlist(ftable, &freqcount); - codetree = shuff_buildtree(inputlist,freqcount); - currnode = codetree; - - while (!feof(fpsource) && (bytesleft > 0)) { + int bitsleft; + + /* Comienzo a decodificar, pues la tabla ya la levante en el decinit */ + if ((fpdest = fopen(shuff->targetfile,"w")) == NULL) return 0; + currnode = shuff->codetree; + + while (!vfeof(shuff->decoderfp) && (shuff->bytesleft > 0)) { /* Leo un buffer de 32 bits */ - if (fread(&codebuffer,sizeof(unsigned long int),1,fpsource) != 1) continue; + if (vfread(&codebuffer,sizeof(unsigned long int),1,shuff->decoderfp) != 1) continue; bitsleft = sizeof(unsigned long int) * 8; /* Proceso el buffer sacando simbolos hasta que se me agote */ - while ((bitsleft > 0) && (bytesleft > 0)) { + while ((bitsleft > 0) && (shuff->bytesleft > 0)) { currnode = shuff_decode_symbols(currnode,codebuffer,&bitsleft,&decoded_symbol); /* Si obtuve un symbolo valido lo emito*/ if (decoded_symbol != 256) { fputc(decoded_symbol,fpdest); - currnode = codetree; - --bytesleft; + currnode = shuff->codetree; + --(shuff->bytesleft); } } } - - fclose(fpsource); - fclose(fpdest); - - /* Free up memory baby yeah */ - free(ftable); - free(inputlist); + + /* Close destination */ + fclose(fpdest); return 1; } -int main(int argc, char* argv[]) -{ - int cflag = 0; - int dflag = 0; - int tflag = 0; - long int volumesize = 0; - int ch; - - while ((ch = getopt(argc, argv, "cdt:")) != -1) { - - switch (ch) { - case 'c': cflag = 1; - break; - - case 'd': dflag = 1; - break; - - case 't': tflag = 1; - volumesize = atoi(optarg); - break; - - default: fprintf(stderr, "Usage: %s [-cdt] sourcefile targetfile\n", argv[0]); - return(2); - } - } - - if ( (argc == 1) || (cflag & dflag) || !(cflag | dflag) || ((argc - optind) < 2) ) { - fprintf(stderr, "Usage: %s [-cdt] sourcefile targetfile\n", argv[0]); - if ((tflag == 1) && (volumesize <= 0)) fprintf(stderr,"Error: The volume size must be a non-zero value\n"); - return (2); - } - - if (cflag == 1) { - /* Comprimo */ - return shuff_encode_file(argv[optind],argv[optind+1]); - } +/** Inicializa un descompresor de huffman */ +HUFF_STATE *shuff_init_decoder(char *inputfile, char *outputfile) +{ + /* Locals */ + HUFF_STATE *shuff = (HUFF_STATE*)malloc(sizeof(HUFF_STATE)); + shuff->freqtable = (t_freq*)malloc(sizeof(t_freq)*256); - if (dflag == 1) { - /* Descomprimo */ - return shuff_decode_file(argv[optind],argv[optind+1]); - } + /* Init fields */ + shuff->codebuffer = 0; + shuff->bitsleft = 0; + shuff->coderfp = NULL; + shuff->targetfile = NULL; + shuff->sourcefile = (char*)malloc(sizeof(char)*(strlen(inputfile)+1)); + strcpy(shuff->sourcefile,inputfile); + if (outputfile != NULL) { + shuff->targetfile = (char*)malloc(sizeof(char)*(strlen(outputfile)+1)); + strcpy(shuff->targetfile,outputfile); + } + + /* Levanto cuantos bytes debo decodificar y la freqtable */ + if ((shuff->decoderfp = vfopen(shuff->sourcefile,"r",0)) == NULL) return NULL; + vfread(&(shuff->bytesleft),sizeof(unsigned long int),1,shuff->decoderfp); + vfread(shuff->freqtable,sizeof(t_freq),256,shuff->decoderfp); + /* Armo el arbol de huffman que uso para decodificar */ + shuff->codetree = shuff_buildtree(shuff->freqtable); + + return shuff; +} + +/** Inicializa compresor de huffman por archivo */ +HUFF_STATE *shuff_init_encoder_byfile(char *inputfile, char *outputfile, long volsize) +{ + /* Locals */ + HUFF_STATE *fshuff = (HUFF_STATE*)malloc(sizeof(HUFF_STATE)); + int i; + + /* Inicializo la estructura para trabajar con Huff Static by File */ + fshuff->coderfp = NULL; + fshuff->decoderfp = NULL; + fshuff->sourcefile = (char*)malloc(sizeof(char)*(strlen(inputfile)+1)); + fshuff->targetfile = (char*)malloc(sizeof(char)*(strlen(outputfile)+1)); + strcpy(fshuff->sourcefile,inputfile); + strcpy(fshuff->targetfile,outputfile); + fshuff->volsize = volsize; + fshuff->bychunk = 0; + fshuff->canonic = 0; + fshuff->freqtable = (t_freq*)malloc(sizeof(t_freq)*256); + for (i = 0; i < 256; ++i) fshuff->freqtable[i] = 0; + fshuff->sumfreq = 0; + fshuff->codetree = NULL; + + return fshuff; +} + +/** Inicializa compresor de huffman de a chunks */ +HUFF_STATE *shuff_init_encoder_bychunk(char *outputfile, long volsize) +{ + /* Locals */ + HUFF_STATE *cshuff = (HUFF_STATE*)malloc(sizeof(HUFF_STATE)); + int i; + + /* Inicializo la estructura para trabajar con Huff Static by Chunks */ + cshuff->decoderfp = NULL; + cshuff->sourcefile = (char*)malloc(sizeof(char)*(strlen(outputfile)+2)); + cshuff->targetfile = (char*)malloc(sizeof(char)*(strlen(outputfile)+1)); + strcpy(cshuff->targetfile,outputfile); + strcpy(cshuff->sourcefile,outputfile); + strcat(cshuff->sourcefile,"~"); + cshuff->volsize = volsize; + cshuff->bychunk = 1; + cshuff->canonic = 0; + cshuff->freqtable = (t_freq*)malloc(sizeof(t_freq)*256); + for (i = 0; i < 256; ++i) cshuff->freqtable[i] = 0; + cshuff->sumfreq = 0; + cshuff->codetree = NULL; + + /* Abrimos un archivo temporal para ir tirando los chunks */ + if ((cshuff->coderfp = fopen(cshuff->sourcefile,"w")) == NULL) return NULL; + + return cshuff; +} + +/** Carga un modelo estadistico para huffman */ +int shuff_loadmodel(HUFF_STATE *shuff, char *modelfile) { + + FILE *fp; + + if ((shuff) && (shuff->freqtable) && (modelfile)) { + /* Cargo el modelo de disco */ + if ((fp = fopen(modelfile,"r")) == NULL) return 0; + if (fread(shuff->freqtable,sizeof(t_freq),256,fp) != 256) return 0; + shuff->canonic = 1; + if (fp) fclose(fp); + return 1; + } + return 0; +} + +/** Graba un modelo estadístico de huffman */ +int shuff_savemodel(HUFF_STATE *shuff) { + + FILE *fp; + char *auxfilename; + char *stopchar; + + if ((shuff) && (shuff->targetfile) && (shuff->freqtable)) { + /* Preparo el nombre del archivo con la tabla */ + auxfilename = (char*)malloc(strlen(shuff->targetfile)+1); + stopchar = strrchr(shuff->targetfile,'.'); + strncpy(auxfilename,shuff->targetfile,stopchar - shuff->targetfile); + auxfilename[stopchar - shuff->targetfile] = 0; + strcat(auxfilename,".ftb"); + /* Lo creamos y dumpeamos la tabla de frecuencias (modelo) */ + if ((fp = fopen(auxfilename,"w")) == NULL) return 0; + fwrite(shuff->freqtable,sizeof(t_freq),256,fp); + if (fp) fclose(fp); + + return 1; + } return 0; } + +/** Desinicializa un compresor de huffman */ +void shuff_deinit_encoder(HUFF_STATE *shuff) +{ + /* Libero mallocs y cierro archivos */ + if (shuff->freqtable) free(shuff->freqtable); + if (shuff->coderfp) fclose(shuff->coderfp); + if (shuff->bychunk) unlink(shuff->sourcefile); + if (shuff->sourcefile) free(shuff->sourcefile); + if (shuff->targetfile) free(shuff->targetfile); + + /* Destruyo recursivamente el arbol de codigos */ + if (shuff->codetree) shuff_destroy_tree(shuff->codetree); +} + +/** Desinicializa un descompresor de huffman */ +void shuff_deinit_decoder(HUFF_STATE *shuff) +{ + /* Libero mallocs y cierro archivos */ + if (shuff->freqtable) free(shuff->freqtable); + if (shuff->sourcefile != NULL) free(shuff->sourcefile); + if (shuff->targetfile != NULL) free(shuff->targetfile); + if (shuff->decoderfp != NULL) vfclose(shuff->decoderfp); + + /* Destruyo recursivamente el arbol de codigos */ + if (shuff->codetree) shuff_destroy_tree(shuff->codetree); +}