/* xutil.c - Various wrapper functions to abort on error.
 *
 * Copyright © 2009 Carl Worth
 *
 * This program is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program.  If not, see http://www.gnu.org/licenses/ .
 *
 * Author: Carl Worth <cworth@cworth.org>
 */

#define _GNU_SOURCE /* For strndup */
#include "notmuch-private.h"

#include <stdio.h>

void *
xcalloc (size_t nmemb, size_t size)
{
    void *ret;

    ret = calloc (nmemb, size);
    if (ret == NULL) {
	fprintf (stderr, "Out of memory.\n");
	exit (1);
    }

    return ret;
}

void *
xmalloc (size_t size)
{
    void *ret;

    ret = malloc (size);
    if (ret == NULL) {
	fprintf (stderr, "Out of memory.\n");
	exit (1);
    }

    return ret;
}

void *
xrealloc (void *ptr, size_t size)
{
    void *ret;

    ret = realloc (ptr, size);
    if (ret == NULL) {
	fprintf (stderr, "Out of memory.\n");
	exit (1);
    }

    return ret;
}

char *
xstrdup (const char *s)
{
    char *ret;

    ret = strdup (s);
    if (ret == NULL) {
	fprintf (stderr, "Out of memory.\n");
	exit (1);
    }

    return ret;
}

/* Mac OS X don't have strndup even if _GNU_SOURCE is defined */
char *
_notmuch_strndup (const char *s, size_t n)
{
    size_t len = strlen (s);
    char *ret;

    if (len <= n)
       return strdup (s);

    ret = malloc(n + 1);
    strncpy(ret, s, n);
    ret[n] = '\0';
    return ret;
}

/* getline implementation is copied from glibc. */

#ifndef SIZE_MAX
# define SIZE_MAX ((size_t) -1)
#endif
#ifndef SSIZE_MAX
# define SSIZE_MAX ((ssize_t) (SIZE_MAX / 2))
#endif

ssize_t
_notmuch_getline (char **lineptr, size_t *n, FILE *fp)
{
    ssize_t result;
    size_t cur_len = 0;

    if (lineptr == NULL || n == NULL || fp == NULL)
    {
       errno = EINVAL;
       return -1;
    }

    if (*lineptr == NULL || *n == 0)
    {
       *n = 120;
       *lineptr = (char *) malloc (*n);
       if (*lineptr == NULL)
       {
           result = -1;
           goto end;
       }
    }

    for (;;)
    {
       int i;

       i = getc (fp);
       if (i == EOF)
       {
           result = -1;
           break;
       }

       /* Make enough space for len+1 (for final NUL) bytes.  */
       if (cur_len + 1 >= *n)
       {
           size_t needed_max =
               SSIZE_MAX < SIZE_MAX ? (size_t) SSIZE_MAX + 1 : SIZE_MAX;
           size_t needed = 2 * *n + 1;   /* Be generous. */
           char *new_lineptr;

           if (needed_max < needed)
               needed = needed_max;
           if (cur_len + 1 >= needed)
           {
               result = -1;
               goto end;
           }

           new_lineptr = (char *) realloc (*lineptr, needed);
           if (new_lineptr == NULL)
           {
               result = -1;
               goto end;
           }

           *lineptr = new_lineptr;
           *n = needed;
       }

       (*lineptr)[cur_len] = i;
       cur_len++;

       if (i == '\n')
           break;
    }
    (*lineptr)[cur_len] = '\0';
    result = cur_len ? (ssize_t) cur_len : result;

end:
    return result;
}

char *
xstrndup (const char *s, size_t n)
{
    char *ret;

    ret = strndup (s, n);
    if (ret == NULL) {
	fprintf (stderr, "Out of memory.\n");
	exit (1);
    }

    return ret;
}

void
xregcomp (regex_t *preg, const char *regex, int cflags)
{
    int rerr;

    rerr = regcomp (preg, regex, cflags);
    if (rerr) {
	size_t error_size = regerror (rerr, preg, NULL, 0);
	char *error = xmalloc (error_size);

	regerror (rerr, preg, error, error_size);
	INTERNAL_ERROR ("compiling regex %s: %s\n",
			regex, error);
    }
}

int
xregexec (const regex_t *preg, const char *string,
	  size_t nmatch, regmatch_t pmatch[], int eflags)
{
    unsigned int i;
    int rerr;

    rerr = regexec (preg, string, nmatch, pmatch, eflags);
    if (rerr)
	return rerr;

    for (i = 0; i < nmatch; i++) {
	if (pmatch[i].rm_so == -1)
	    INTERNAL_ERROR ("matching regex against %s: Sub-match %d not found\n",
			    string, i);
    }

    return 0;
}