alsa-utils/alsamixer/utils.c
Jaroslav Kysela 56f2064bb4 alsamixer: remove wrong free(buf) call in read_file()
Signed-off-by: Jaroslav Kysela <perex@perex.cz>
2020-07-01 16:16:24 +02:00

148 lines
3.8 KiB
C

/*
* utils.c - multibyte-string helpers
* Copyright (c) Clemens Ladisch <clemens@ladisch.de>
*
* 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 2 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/>.
*/
#ifndef _XOPEN_SOURCE
#define _XOPEN_SOURCE
#endif
#include "aconfig.h"
#include <limits.h>
#include <stdlib.h>
#include <string.h>
#include <wchar.h>
#include <errno.h>
#include <stdio.h>
#include "utils.h"
#include "mem.h"
/*
* mbs_at_width - compute screen position in a string
*
* For displaying strings on the screen, we have to know how many character
* cells are occupied. This function calculates the position in a multibyte
* string that is at a desired position.
*
* Parameters:
* s: the string
* width: on input, the desired number of character cells; on output, the actual
* position, in character cells, of the return value
* dir: -1 or 1; in which direction to round if a multi-column character goes
* over the desired width
*
* Return value:
* Pointer to the place in the string that is as near the desired width as
* possible. If the string is too short, the return value points to the
* terminating zero. If the last character is a multi-column character that
* goes over the desired width, the return value may be one character cell
* earlier or later than desired, depending on the dir parameter.
* In any case, the return value points after any zero-width characters that
* follow the last character.
*/
const char *mbs_at_width(const char *s, int *width, int dir)
{
size_t len;
wchar_t wc;
int bytes;
int width_so_far, w;
if (*width <= 0)
return s;
mbtowc(NULL, NULL, 0); /* reset shift state */
len = strlen(s);
width_so_far = 0;
while (len && (bytes = mbtowc(&wc, s, len)) > 0) {
w = wcwidth(wc);
if (width_so_far + w > *width && dir < 0)
break;
if (w >= 0)
width_so_far += w;
s += bytes;
len -= bytes;
if (width_so_far >= *width) {
while (len && (bytes = mbtowc(&wc, s, len)) > 0) {
w = wcwidth(wc);
if (w != 0)
break;
s += bytes;
len -= bytes;
}
break;
}
}
*width = width_so_far;
return s;
}
/*
* get_mbs_width - compute screen width of a string
*/
unsigned int get_mbs_width(const char *s)
{
int width;
width = INT_MAX;
mbs_at_width(s, &width, 1);
return width;
}
/*
* get_max_mbs_width - get width of longest string in an array
*/
unsigned int get_max_mbs_width(const char *const *s, unsigned int count)
{
unsigned int max_width, i, len;
max_width = 0;
for (i = 0; i < count; ++i) {
len = get_mbs_width(s[i]);
if (len > max_width)
max_width = len;
}
return max_width;
}
#define MAX_FILE_SIZE 1048576
char *read_file(const char *file_name, unsigned int *file_size)
{
FILE *f;
int err;
char *buf;
unsigned int allocated = 2048;
unsigned int bytes_read;
f = fopen(file_name, "r");
if (!f) {
err = errno;
errno = err;
return NULL;
}
*file_size = 0;
buf = NULL;
do {
allocated *= 2;
buf = crealloc(buf, allocated);
bytes_read = fread(buf + *file_size, 1, allocated - *file_size, f);
*file_size += bytes_read;
} while (*file_size == allocated && allocated < MAX_FILE_SIZE);
fclose(f);
if (*file_size > 0 && buf[*file_size - 1] != '\n' && *file_size < allocated) {
buf[*file_size] = '\n';
++*file_size;
}
return buf;
}