syn_lex.h

这是一个语法分析器 这是一个语法分析器

#ifndef SYN_LEX_H_INCLUDED
#define SYN_LEX_H_INCLUDED

void error(char *str)
{
    printf("Error: %s!\n", str);
    exit(1);
}

int load_init()
{
    tcount = 0;
    scount = 0;
    pcount = 0;
    strcpy(file, "test.txt");
    fp = fopen(file, "rb+");
    if (fp == NULL)
    {
        printf("open file error!\n");
        return -1;
    }
    return 0;
}

void add_string(char * str)
{
    int len = 0;
    len = strlen(str);
    sign_string[scount] = (char*)malloc(len+1);
    strcpy(sign_string[scount], str);
    sign_string[scount][len] = 0;
}

int get_id(char *str)
{
    int i = 0;
    for(i = 0; i < scount; i++)
    {
        if (strcmp(str, sign_string[i]) == 0)
            return i;
    }
    return -1;
}

void load_sign()
{
    int state = 0;
    char buf[SIZE];
    while(1)
    {
        switch(state)
        {
        case 0:
            fscanf(fp, "%s", buf);
            if (strcmp(buf, DEPART) == 0)
                state = 1;
            else
            {
                add_string(buf);
                tcount++;
                scount++;
            }
            break;
        case 1:
            fscanf(fp, "%s", buf);
            if (strcmp(buf, DEPART) == 0)
                state = 2;
            else
            {
                add_string(buf);
                scount++;
            }
            break;
        case 2:
            return;
        }
    }
    return;
}

void load_produce()
{
    int state = 0;
    char buf[SIZE];
    int id = 0;
    struct sign_node *cptr = NULL;
    struct sign_node *temp = NULL;

    while(1)
    {
        switch(state)
        {
        case 0:
            fscanf(fp, "%s", buf);
            if (strcmp(buf, DEPART) == 0)
                return;
            id = get_id(buf);
            if (id == -1)
            {
                printf("%d ", count);
                strcat(buf, " left");
                error(buf);
            }
            else
            {
                sign[pcount].id = id;
                sign[pcount].next = NULL;
                cptr = &sign[pcount];
                pcount++;
                state = 1;
            }
            break;
        case 1:
            fscanf(fp, "%s", buf);
            if (strcmp(buf, "-->") == 0)
                state = 2;
            else
                error("-->");
            break;
        case 2:
            fscanf(fp, "%s", buf);
            if (strcmp(buf, "\\") == 0)
            {
                count++;
                state = 0;
            }
            else
            {
                temp = (struct sign_node *)malloc(sizeof(struct sign_node));
                id = get_id(buf);
                if (id == -1)
                {
                    strcat(buf, " right");
                    error(buf);
                }
                else
                {
                    temp->id = id;
                    temp->next = NULL;
                    cptr->next = temp;
                    cptr = temp;
                }
            }
            break;
        }
    }
}

void load()
{
    load_sign();
    load_produce();
    fclose(fp);
}

void free_produce(int pos)
{
    struct sign_node *p = NULL;
    p = sign[pos].next;
    while(p != NULL)
    {
        sign[pos].next = p->next;
        free(p);
        p = sign[pos].next;
    }
}

void print_sign(FILE *stream)
{
    int i = 0;
    fprintf(stream,"print signs:\n");
    for(i = 0; i < scount; i++)
        fprintf(stream,"%s\n", sign_string[i]);
}

void print_single_produce(FILE *stream, int num)
{
    struct sign_node *p = NULL;
    p = &sign[num];
    fprintf(stream, "%s -> ", sign_string[p->id]);
    p = p -> next;
    while(p != NULL)
    {
        fprintf(stream, "%s ", sign_string[p->id]);
        p = p -> next;
    }
    fprintf(stream, "\n");
}

void print_all_produce(FILE *stream)
{
    int i = 0;
    fprintf(stream, "print produce:\n");
    for(i = 0; i < pcount; i++)
    {
        print_single_produce(stream, i);
    }
}

#endif // SYN_LEX_H_INCLUDED