ref: 9f1e329ece930416249b9cfc0a425d372a6a3305
dir: /SDL_Examples/include/stringutil.h/
#include <string.h>
#include <stdlib.h>
#include <stdio.h>
#include <ctype.h>
//Before we get on, "stringutil.h" is the most C-ish name for a source code file ever, amirite?
#ifndef STRUTIL_ALLOC
#define STRUTIL_ALLOC(s) malloc(s)
#endif
#ifndef STRUTIL_FREE
#define STRUTIL_FREE(s) free(s)
#endif
#ifndef STRUTIL_REALLOC
#define STRUTIL_REALLOC(s, t) realloc(s,t)
#endif
#ifndef STRUTIL_NO_SHORT_NAMES
#define strcata strcatalloc
#define strcataf1 strcatallocf1
#define strcataf2 strcatallocf2
#define strcatafb strcatallocfb
#endif
//Strcat but with malloc.
static inline char* strcatalloc(const char* s1, const char* s2){
char* d = NULL; d = STRUTIL_ALLOC(strlen(s1) + strlen(s2) + 1);
if(d){
strcpy(d, s1);
strcat(d, s2);
}
return d;
}
//Free the first argument.
static inline char* strcatallocf1(char* s1, const char* s2){
char* d = STRUTIL_REALLOC(s1, strlen(s1) + strlen(s2) + 1);
//char* d = NULL; d = STRUTIL_ALLOC(strlen(s1) + strlen(s2) + 1);
if(d){
//strcpy(d, s1);
strcat(d, s2);
}
//STRUTIL_FREE(s1);
return d;
}
//Free the second argument.
static inline char* strcatallocf2(const char* s1, char* s2){
char* d = NULL; d = STRUTIL_ALLOC(strlen(s1) + strlen(s2) + 1);
if(d){
strcpy(d, s1);
strcat(d, s2);
}
STRUTIL_FREE(s2);
return d;
}
//Free both arguments
static inline char* strcatallocfb(char* s1, char* s2){
char* d = NULL; d = STRUTIL_ALLOC(strlen(s1) + strlen(s2) + 1);
if(d){
strcpy(d, s1);
strcat(d, s2);
}
STRUTIL_FREE(s1);
STRUTIL_FREE(s2);
return d;
}
//Convert a non-null-terminated URL into a null terminated one.
static inline char* str_null_terminated_alloc(const char* in, unsigned int len){
char* d = NULL; d = malloc(len+1);
if(d){
memcpy(d,in,len);
d[len] = '\0';
}
return d;
}
static inline unsigned int strprefix(const char *pre, const char *str)
{
size_t lenpre = strlen(pre),
lenstr = strlen(str);
return lenstr < lenpre ? 0 : memcmp(pre, str, lenpre) == 0;
}
//Someone once said sub-string search was an O(n^2) algorithm. What the hell?
static inline long long strfind(const char* text, const char* subtext){
long long ti = 0;
long long si = 0;
long long st = strlen(subtext);
for(;text[ti] != '\0';ti++){
if(text[ti] == subtext[si]) {
si++;
if(subtext[si] == '\0') return (ti - st)+1;
}else {
si = 0;
if(subtext[si] == '\0') return (ti - st);
}
}
return -1;
}
//Read file until terminator character is found.
//Returns the number of characters copied.
static inline unsigned long long read_until_terminator(FILE* f, char* buf, const unsigned long long buflen, char terminator){
unsigned long long i = 0;
char c;
for(i = 0; i < (buflen-1); i++)
{
if(feof(f))break;
c = fgetc(f);
if(c == terminator)break;
buf[i] = c;
}
buf[buflen-1] = '\0'; //READ_UNTIL_TERMINATOR ALWAYS RETURNS A VALID STRING!
return i;
}
//Same as above but allocates memory to guarantee it can hold the entire thing. Grows naturally.
static inline char* read_until_terminator_alloced(FILE* f, unsigned long long* lenout, char terminator, unsigned long long initsize){
char c;
char* buf = STRUTIL_ALLOC(initsize);
if(!buf) return NULL;
unsigned long long bcap = initsize;
unsigned long long blen = 0;
while(1){
if(feof(f)){break;}
c = fgetc(f);
if(c == terminator) {break;}
if(blen == (bcap-1)) //Grow the buffer.
{
bcap<<=1;
char* bufold = buf;
buf = STRUTIL_REALLOC(buf, bcap);
if(!buf){free(bufold); return NULL;}
}
buf[blen++] = c;
}
buf[blen] = '\0'; //READ_UNTIL_TERMINATOR ALWAYS RETURNS A VALID STRING!
*lenout = blen;
return buf;
}
static inline void* read_file_into_alloced_buffer(FILE* f, unsigned long long* len){
void* buf = NULL;
if(!f) return NULL;
fseek(f, 0, SEEK_END);
*len = ftell(f);
fseek(f,0,SEEK_SET);
buf = STRUTIL_ALLOC(*len + 1);
if(!buf) return NULL;
fread(buf, 1, *len, f);
((char*)buf)[*len] = '\0';
return buf;
}
//GEK'S SIMPLE TEXT COMPRESSION SCHEMA
/*LIMITATIONS
* Token names must be alphabetic (a-z, A-Z)
* The token mark must be escaped with a backslash.
* Token names which are substrings of other ones must be listed later
*/
static inline char* strencodealloc(const char* inbuf, const char** tokens, unsigned long long ntokens, char esc, char tokmark){
unsigned long long lenin = strlen(inbuf);
char c; unsigned long long i = 0;
char c_str[512] = {0}; //We are going to be sprintf-ing to this buffer.
char* out = NULL;
c_str[0] = esc;
c_str[1] = tokmark;
out = strcatalloc(c_str, "");
c_str[0] = 0;
c_str[1] = 0;
//Write out all the token entries. format is namelength~definition
for(unsigned long long j = 0; j < ntokens; j++){
out = strcataf1(out, tokens[2*j]);
//Write out the length of the token.
snprintf(c_str, 512, "%llu", (unsigned long long)strlen(tokens[2*j+1]));
out = strcataf1(out, c_str);
c_str[0] = tokmark;
c_str[1] = 0;
out = strcataf1(out, c_str);
out = strcataf1(out, tokens[2*j+1]);
}
c_str[0] = esc;
c_str[1] = 0;
out = strcataf1(out, c_str);
//We have now created the header. Now to begin encoding the text.
for(i=0; i<lenin; i++){
for(unsigned long long t = 0; t < ntokens; t++) //t- the token we are processing.
if(strprefix(tokens[t*2+1], inbuf+i)){ //Matched at least one
unsigned long long howmany = 1;
unsigned long long curtoklen = strlen(tokens[t*2+1]); //Length of the current token we are counting
for(unsigned long long h=1;i+h*curtoklen < lenin;h++){
if(strprefix(tokens[t*2+1], inbuf+i+h*curtoklen))
{howmany++;}
else
break; //The number of these things is limited.
}
//We know what token and how many, write it to out
c_str[0] = tokmark;
c_str[1] = 0;
out = strcataf1(out, c_str);
if(howmany > 1){
snprintf(c_str, 512, "%llu", (unsigned long long)howmany);
out = strcataf1(out, c_str);
}
out = strcataf1(out, tokens[t*2]);
i+=howmany*curtoklen;
continue;
}
//Test if we need to escape a sequence.
if(inbuf[i] == esc || inbuf[i] == tokmark){
c_str[0] = esc;
c_str[1] = 0;
out = strcataf1(out, c_str);
}
//We were unable to find a match, just write the character out.
c_str[0] = inbuf[i];
c_str[1] = 0;
out = strcataf1(out, c_str);
}
return out;
}
static inline char* strdecodealloc(char* inbuf){
unsigned long long lenin = strlen(inbuf);
if(lenin < 3) {
//puts("\nToo Short!\n");
return NULL;
}
char esc = inbuf[0]; //The escape character is the first one.
char tokmark = inbuf[1]; //Begin token character.
//printf("Escape is %c, tokmark is %c\n", esc, tokmark);
char c; unsigned long long i = 2;
char c_str[2] = {0,0};
//Our decoded text.
char* out = strcatalloc("","");
//Tokens for replacement, even is the token,
//odd is its definition
char** tokens = NULL;
//unsigned long long* toklens = NULL;
unsigned long long ntokens = 0;
//#define {if(i <= lenin) c = inbuf[i++]; else {goto end;}} {if(i <= lenin) c = inbuf[i++]; else {goto end;}}
//Retrieve the tokens.
{if(i <= lenin) c = inbuf[i++]; else {goto end;}}; //has to occur before the loop.
while(c != esc){ ntokens++;
tokens = STRUTIL_REALLOC(tokens, ntokens * 2 * sizeof(char*));
//toklens = STRUTIL_REALLOC(toklens, ntokens * sizeof(unsigned long long));
//toklens[ntokens-1] = 0;
tokens[(ntokens-1)*2] = strcatalloc("","");
tokens[(ntokens-1)*2+1] = strcatalloc("","");
//name of token is tokens[(ntokens-1)*2] and its definition is tokens[(ntokens-1)*2+1]
//Get the name of the token.
if(!isalpha(c)) goto end; //Error! Can't have Break out.
while(isalpha(c)){
c_str[0] = c;
tokens[(ntokens-1)*2] = strcatallocf1(tokens[(ntokens-1)*2], c_str);
{if(i <= lenin) c = inbuf[i++]; else {goto end;}};
}
//The last retrieve() got us the first digit of the token length.
//Get the length of the token
unsigned long long l = 0;
if(!isdigit(c)) goto end;
while(isdigit(c) && c!=tokmark){
c_str[0] = c;
l *= 10;
l += atoi(c_str);
{if(i <= lenin) c = inbuf[i++]; else {goto end;}};
}
//toklens[ntokens-1] = l;
//We have the name of the token and its length, the last {if(i <= lenin) c = inbuf[i++]; else {goto end;}} got us the token character (~ in my example)
//Now we can grab the token definition.
for(unsigned long long vv = 0; vv < l; vv++){
{if(i <= lenin) c = inbuf[i++]; else {goto end;}};
c_str[0] = c;
tokens[(ntokens-1)*2+1] = strcatallocf1(tokens[(ntokens-1)*2+1], c_str);
}
{if(i <= lenin) c = inbuf[i++]; else {goto end;}};
// printf("\nTOKEN %s IS %s, length %llu",tokens[(ntokens-1)*2] ,tokens[(ntokens-1)*2+1], l);
}
//puts("\nREACHED ESCAPE CHARACTER.");
//Now we attempt to build our string
{if(i <= lenin) c = inbuf[i++]; else {goto end;}};
long long doescape = 0;
while(i<=lenin){
if(!doescape && c==esc){
doescape=1;{if(i <= lenin) c = inbuf[i++]; else {goto end;}};continue;
}
if(!doescape && c==tokmark){
//Handle digits prefixing a token.
unsigned long long l = 0;
{if(i <= lenin) c = inbuf[i++]; else {goto end;}};
if(isdigit(c))
while(isdigit(c)){
c_str[0] = c;
l *= 10;
l += atoi(c_str);
{if(i <= lenin) c = inbuf[i++]; else {goto end;}};
}
else {l=1;}
i--;
for(unsigned long long t = 0; t < ntokens; t++)
if(strprefix(tokens[t*2], inbuf+i)){
//MATCH!
for(unsigned long long q = 0; q < l; q++)
out = strcatallocf1(out, tokens[t*2+1]);
i+=strlen(tokens[t*2]);
break; //break out of the for.
}
if(i<=lenin) {if(i <= lenin) c = inbuf[i++]; else {goto end;}};
continue;
}else{
c_str[0] = c;
out = strcatallocf1(out, c_str);
doescape = 0;
{if(i <= lenin) c = inbuf[i++]; else {goto end;}};
}
}
end:
if(tokens){
for(unsigned long long j = 0; j < ntokens; j++)
{STRUTIL_FREE(tokens[j*2]);STRUTIL_FREE(tokens[j*2+1]);}
STRUTIL_FREE(tokens);
}
//if(toklens)STRUTIL_FREE(toklens);
return out;
}