slime/src/helpers.c

#define new(type) (type*)malloc(sizeof(type))
#define nullptr NULL

#define concat_( a, b) a##b
#define label(prefix, lnum) concat_(prefix,lnum)
#define try                                     \
    if (1)                                      \
        goto label(body,__LINE__);              \
    else                                        \
        while (1)                               \
            if (1) {                            \
                if(error) return 0;             \
                break;                          \
            }                                   \
            else label(body,__LINE__):          

typedef enum { false, true } bool;

int string_equal(char* a, char* b) {
    return !strcmp(a, b);
}

// asprintf implementation
int _vscprintf_so(const char * format, va_list pargs) {
    int retval;
    va_list argcopy;
    va_copy(argcopy, pargs);
    retval = vsnprintf(nullptr, 0, format, argcopy);
    va_end(argcopy);
    return retval;
}

int vasprintf(char **strp, const char *fmt, va_list ap) {
    int len = _vscprintf_so(fmt, ap);
    if (len == -1) return -1;
    char *str = malloc((size_t) len + 1);
    if (!str) return -1;
    int r = vsnprintf(str, len + 1, fmt, ap); /* "secure" version of vsprintf */
    if (r == -1) return free(str), -1;
    *strp = str;
    return r;
}

int asprintf(char *strp[], const char *fmt, ...) {
    va_list ap;
    va_start(ap, fmt);
    int r = vasprintf(strp, fmt, ap);
    va_end(ap);
    return r;
}
// asprintf implementation end

char* read_entire_file (char* filename) {
    char *fileContent = nullptr;
    FILE *fp = fopen(filename, "r");
    if (fp) {
        /* Go to the end of the file. */
        if (fseek(fp, 0L, SEEK_END) == 0) {
            /* Get the size of the file. */
            long bufsize = ftell(fp);
            if (bufsize == -1) {
                fputs("Empty file", stderr);
                goto closeFile;
            }

            /* Go back to the start of the file. */
            if (fseek(fp, 0L, SEEK_SET) != 0) {
                fputs("Error reading file", stderr);
                goto closeFile;
            }

            /* Allocate our buffer to that size. */
            fileContent = malloc(sizeof(char) * (bufsize) +1);

            /* Read the entire file into memory. */
            size_t newLen = fread(fileContent, sizeof(char), bufsize, fp);
            fileContent[bufsize-1] = '\0';
            if ( ferror( fp ) != 0 ) {
                fputs("Error reading file", stderr);
            }
        }
      closeFile:
        fclose(fp);
    }

    return fileContent;
    /* Don't forget to call free() later! */
}

char* read_line() {
    char* line = malloc(100), * linep = line;
    size_t lenmax = 100, len = lenmax;
    int c;

    if(line == NULL)
        return NULL;

    for(;;) {
        c = fgetc(stdin);
        if(c == EOF)
            break;

        if(--len == 0) {
            len = lenmax;
            char * linen = realloc(linep, lenmax *= 2);

            if(linen == NULL) {
                free(linep);
                return NULL;
            }
            line = linen + (line - linep);
            linep = linen;
        }

        if((*line++ = c) == '\n')
            break;
    }
    *line--; // we dont want the \n actually
    *line = '\0';
    return linep;
}