i3status/src/general.c

120 lines
2.8 KiB
C

// vim:ts=4:sw=4:expandtab
#include <config.h>
#include <sys/types.h>
#include <string.h>
#include <stdarg.h>
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <glob.h>
#include <sys/fcntl.h>
#include <sys/stat.h>
#include "i3status.h"
#define exit_if_null(pointer, ...) \
{ \
if (pointer == NULL) \
die(__VA_ARGS__); \
}
/*
* Reads size bytes into the destination buffer from filename.
*
* On success, true is returned. Otherwise, false is returned and the content
* of destination is left untouched.
*
*/
bool slurp(const char *filename, char *destination, int size) {
int fd;
if ((fd = open(filename, O_RDONLY)) == -1)
return false;
/* We need one byte for the trailing 0 byte */
int n = read(fd, destination, size - 1);
if (n != -1)
destination[n] = '\0';
(void)close(fd);
return n != -1;
}
/*
* This function resolves ~ in pathnames.
* It may resolve wildcards in the first part of the path, but if no match
* or multiple matches are found, it just returns a copy of path as given.
*
*/
char *resolve_tilde(const char *path) {
static glob_t globbuf;
char *head, *tail, *result = NULL;
tail = strchr(path, '/');
head = strndup(path, tail ? (size_t)(tail - path) : strlen(path));
int res = glob(head, GLOB_TILDE, NULL, &globbuf);
free(head);
/* no match, or many wildcard matches are bad */
if (res == GLOB_NOMATCH || globbuf.gl_pathc != 1)
result = sstrdup(path);
else if (res != 0) {
die("glob() failed");
} else {
head = globbuf.gl_pathv[0];
result = scalloc(strlen(head) + (tail ? strlen(tail) : 0) + 1);
strcpy(result, head);
if (tail) {
strcat(result, tail);
}
}
globfree(&globbuf);
return result;
}
char *sstrdup(const char *str) {
if (str == NULL) {
return NULL;
}
char *result = strdup(str);
exit_if_null(result, "Error: out of memory (strdup())\n");
return result;
}
void *scalloc(size_t size) {
void *result = calloc(size, 1);
exit_if_null(result, "Error: out of memory (calloc(%zu))\n", size);
return result;
}
/*
* Skip the given character for exactly 'amount' times, returns
* a pointer to the first non-'character' character in 'input'.
*
*/
char *skip_character(char *input, char character, int amount) {
char *walk;
size_t len = strlen(input);
int blanks = 0;
for (walk = input; ((size_t)(walk - input) < len) && (blanks < amount); walk++)
if (*walk == character)
blanks++;
return (walk == input ? walk : walk - 1);
}
/*
* Write errormessage to statusbar and exit
*
*/
void die(const char *fmt, ...) {
va_list ap;
va_start(ap, fmt);
(void)vfprintf(stderr, fmt, ap);
va_end(ap);
exit(EXIT_FAILURE);
}