在没有strtok / lexer的情况下将字符串解析为标记

Question

I want to parse a string into an array of tokens . '\\n' and ';' are delimiters , for eg :

hello;hello
world

should be converted to an array containing: {"hello","hello","world"} .

I tried many different methods for doing this and always I fail (since it needs a dynamic array of char * I have trouble with implementing it).

Please note that I cannot use strtok or lexical analyzer.

How may I do this ? Any points ?

EDIT : here is one of methods I tried to use but I get segmentation fault (maybe a memory access issue somewhere in my code) :

#include <stdio.h>
#include <malloc.h>
#include <fcntl.h>
#include <string.h>

typedef struct { 
    int fd;
    char *path;
    int size;
    char *mem;
    struct stat st;
} file;

file *readfile(char *path) {
    file *a=malloc(sizeof(file));
    a->path=path;
    a->fd=open(a->path,O_RDONLY);
    if(a->fd<0) return 0;
    fstat(a->fd,&a->st);
    a->size=a->st.st_size;
    a->mem=malloc(a->size);
    read(a->fd,a->mem,a->size);
    return a;
}

void releasefile(file *a) {
    free(a->mem);
    close(a->fd);
    free(a);
}

char **parse(int *w,file *a) {
    int i,j=0;
    w=0;
    for(i=0;i<=a->size;i++) {
        if(a->mem[i]=='\n' || a->mem[i]==';') { a->mem[i]='\0'; j++; }
    }
    char **out=malloc(sizeof(char *)*j);
    for(i=0;i<=a->size;i++) {
       if(a->mem[i-1]!='\0') continue;
       out[*w]=malloc(strlen(a->mem+i)+1);
       memcpy(out[*w],a->mem+i,strlen(a->mem+i)+1);
       w++;
           return out;
}

int main(int argc,char **argv) {
    file *a=readfile(argv[1]);
    int *w=malloc(sizeof(int));
    char **tokens=parse(w,a);
    int i;
    for(i=0;i<=*w;i++) {
        puts(tokens[i]);
        }
        releasefile(a);

    // ATM no need to check for mem leaks :)

}

Algorithm description : read file, put \\0 where you see a delimiter, start and push tokens seprated by \\0 into an array.

Answer 1

What has happened to computer science?

Anyway write a FSA - http://en.wikipedia.org/wiki/Finite-state_machine

Can do this using a table