X-Git-Url: https://git.llucax.com/z.facultad/75.06/jacu.git/blobdiff_plain/d5a4d5447b65cfb33f907f0422d970ed880d82a6..1b23d92c000adeebfb1b68b9323b7df1c225614c:/src/statichuff/statichuff.c?ds=sidebyside

diff --git a/src/statichuff/statichuff.c b/src/statichuff/statichuff.c
index e1dfe35..2fed829 100644
--- a/src/statichuff/statichuff.c
+++ b/src/statichuff/statichuff.c
@@ -1,12 +1,10 @@
 
 #include "statichuff.h"
-#include <stdlib.h>
 
 void putbit(char bit, char restart, char flush, FILE *fp)
 {
 	static unsigned long int bits_buffer = 0;
-	static unsigned char bits_used = 0;
-	int i;
+	static unsigned char bits_used = 0;	
 
 	/* me obligan a emitir el output */
 	if ((flush == 1) && (bits_used > 0)) {
@@ -43,10 +41,10 @@ void shuff_cpynode(SHUFFNODE *node1, SHUFFNODE *node2)
 	node1->rchild = node2->rchild;	
 }
 
-int shuff_compnode(SHUFFNODE *node1, SHUFFNODE *node2)
+int shuff_compnode(const void *node1, const void *node2)
 {	
-	if (node1->freq < node2->freq) return 1;
-	if (node1->freq > node2->freq) return -1;
+	if (((SHUFFNODE*)node1)->freq < ((SHUFFNODE*)node2)->freq) return 1;
+	if (((SHUFFNODE*)node1)->freq > ((SHUFFNODE*)node2)->freq) return -1;
 	return 0;
 }
 
@@ -120,9 +118,8 @@ SHUFFNODE *shuff_buildlist(t_freq *freqtable, int *nonzerofreqs)
 SHUFFNODE *shuff_buildtree(SHUFFNODE *list, int listcount)
 {
 	SHUFFNODE *lastsymbol = list+(listcount-1);
-	SHUFFNODE *node1,*node2,*fictnode;
+	SHUFFNODE *node1,*node2;
 
-	/* Ordenamos inicialmente la inputlist para tomar las dos freqs min */
 	while (lastsymbol > list) {		
 		/* Ordeno la lista por frecuencia descendente */
 		qsort(list,listcount,sizeof(SHUFFNODE),shuff_compnode);				
@@ -240,10 +237,10 @@ int shuff_encode_file(char *inputfile, char *outputfile)
 	SHUFFNODE *inputlist;
 	SHUFFNODE *codetree;
 	SHUFFCODE *codetable = (SHUFFCODE*)malloc(sizeof(SHUFFCODE)*256);
-	int freqcount = 0,i;
+	int freqcount = 0;
 	
 	/* Armamos la tabla de frecuencias */
-	if (!shuff_scanfreq(inputfile,freqtable)) return -1;
+	if (!shuff_scanfreq(inputfile,freqtable)) return 0;
 	
 	/* Armo el input list y genero el arbol de huffman */
 	inputlist = shuff_buildlist(freqtable, &freqcount);
@@ -252,45 +249,81 @@ int shuff_encode_file(char *inputfile, char *outputfile)
 	/* Armo la tabla de codigos prefijos para el encoder */
 	shuff_zerocodes(codetable);
 	shuff_buildcodes(codetable,codetree,0,0);
-	shuff_printcodes(codetable,freqtable);
+	/*shuff_printcodes(codetable,freqtable);*/
 
 	/* Encodeo byte per byte */
 	shuff_encode_symbols(freqtable,codetable,inputfile,outputfile);
+	
+	/* Free up memory baby yeah */
+	free(freqtable);
+	free(inputlist);	
+	free(codetable);
+	
+	return 1;
+}
+
+SHUFFNODE *shuff_decode_symbols(SHUFFNODE *entrynode, unsigned long int buffer, 
+							 int *bitsleft, unsigned short int *symbol)
+{
+	char bit = 0;
+		
+	/* Levanto el symbolo y si es uno valido, devuelvo */
+	*symbol = entrynode->symbol;
+	if (*symbol != 256) return entrynode;		
+	if (*bitsleft == 0) return entrynode;
+		
+	/* Obtengo otro bit a procesar y me muevo en el arbol */
+	bit = (buffer >> ((*bitsleft)-1)) & 1;	
+	--(*bitsleft);
+	if (bit == 0) return shuff_decode_symbols(entrynode->lchild,buffer,bitsleft,symbol);
+	else return shuff_decode_symbols(entrynode->rchild,buffer,bitsleft,symbol);
 }
 
-int shuff_decode(char *inputfile, char *outputfile)
+int shuff_decode_file(char *inputfile, char *outputfile)
 {
 	SHUFFNODE *inputlist;
-	SHUFFNODE *codetree;
+	SHUFFNODE *codetree,*currnode;
 	t_freq *ftable = (t_freq*)malloc(sizeof(t_freq)*256);
-	unsigned long int bytesleft;
+	unsigned long int bytesleft,codebuffer;
 	FILE *fpsource;
 	FILE *fpdest;
-	int i,freqcount = 0;
+	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);
+	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)) {
+		
+		/* Leo un buffer de 32 bits */
+		if (fread(&codebuffer,sizeof(unsigned long int),1,fpsource) != 1) continue;
+		bitsleft = sizeof(unsigned long int) * 8;
+		
+		/* Proceso el buffer sacando simbolos hasta que se me agote */
+		while ((bitsleft > 0) && (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;				
+			}						
+		}		
+	}
 		
 	fclose(fpsource);
 	fclose(fpdest);
 	
+	/* Free up memory baby yeah */
+	free(ftable);
+	free(inputlist);
 	
+	return 1;
 }
 
-int main(int argc, char* argv[])
-{	
-	if (argc == 1) return -1;
-		
-	/* Comprimo */
-	shuff_encode_file(argv[1],"output.shf");	
-
-	/* Decodeo */
-	shuff_decode("output.shf","decoded.dat");
-	
-	return 0;
-}