swayfx/common/readline.c
2018-06-02 08:07:44 -04:00

98 lines
1.9 KiB
C

#define _POSIX_C_SOURCE 200809L
#include "readline.h"
#include "log.h"
#include <stdlib.h>
#include <stdio.h>
char *read_line(FILE *file) {
size_t length = 0, size = 128;
char *string = malloc(size);
char lastChar = '\0';
if (!string) {
wlr_log(L_ERROR, "Unable to allocate memory for read_line");
return NULL;
}
while (1) {
int c = getc(file);
if (c == '\n' && lastChar == '\\'){
--length; // Ignore last character.
lastChar = '\0';
continue;
}
if (c == EOF || c == '\n' || c == '\0') {
break;
}
if (c == '\r') {
continue;
}
lastChar = c;
if (length == size) {
char *new_string = realloc(string, size *= 2);
if (!new_string) {
free(string);
wlr_log(L_ERROR, "Unable to allocate memory for read_line");
return NULL;
}
string = new_string;
}
string[length++] = c;
}
if (length + 1 == size) {
char *new_string = realloc(string, length + 1);
if (!new_string) {
free(string);
return NULL;
}
string = new_string;
}
string[length] = '\0';
return string;
}
char *peek_line(FILE *file, int line_offset, long *position) {
long pos = ftell(file);
size_t length = 0;
char *line = NULL;
for (int i = 0; i <= line_offset; i++) {
ssize_t read = getline(&line, &length, file);
if (read < 0) {
free(line);
line = NULL;
break;
}
if (read > 0 && line[read - 1] == '\n') {
line[read - 1] = '\0';
}
}
if (position) {
*position = ftell(file);
}
fseek(file, pos, SEEK_SET);
return line;
}
char *read_line_buffer(FILE *file, char *string, size_t string_len) {
size_t length = 0;
if (!string) {
return NULL;
}
while (1) {
int c = getc(file);
if (c == EOF || c == '\n' || c == '\0') {
break;
}
if (c == '\r') {
continue;
}
string[length++] = c;
if (string_len <= length) {
return NULL;
}
}
if (length + 1 == string_len) {
return NULL;
}
string[length] = '\0';
return string;
}