i3bar: be less strict about the {"version":1} JSON header

This commit is contained in:
Michael Stapelberg 2012-08-12 18:40:15 +02:00
parent dbe406641f
commit e53405c216
4 changed files with 140 additions and 7 deletions

View File

@ -56,5 +56,6 @@ TAILQ_HEAD(statusline_head, status_block) statusline_head;
#include "xcb.h"
#include "config.h"
#include "libi3.h"
#include "determine_json_version.h"
#endif

View File

@ -0,0 +1,29 @@
/*
* vim:ts=4:sw=4:expandtab
*
* i3bar - an xcb-based status- and ws-bar for i3
* © 2010-2012 Axel Wagner and contributors (see also: LICENSE)
*
* determine_json_version.c: Determines the JSON protocol version based on the
* first line of input from a child program.
*
*/
#ifndef DETERMINE_JSON_VERSION_H_
#define DETERMINE_JSON_VERSION_H_
#include <stdint.h>
/*
* Determines the JSON i3bar protocol version from the given buffer. In case
* the buffer does not contain valid JSON, or no version field is found, this
* function returns -1. The amount of bytes consumed by parsing the header is
* returned in *consumed (if non-NULL).
*
* The return type is an int32_t to avoid machines with different sizes of
* 'int' to allow different values here. Its highly unlikely we ever exceed
* even an int8_t, but still
*
*/
int32_t determine_json_version(const unsigned char *buffer, int length, unsigned int *consumed);
#endif

View File

@ -192,19 +192,18 @@ void stdin_io_cb(struct ev_loop *loop, ev_io *watcher, int revents) {
if (first_line) {
DLOG("Detecting input type based on buffer *%.*s*\n", rec, buffer);
/* Detect whether this is JSON or plain text. */
plaintext = (strncasecmp((char*)buffer, "{\"version\":", strlen("{\"version\":")) != 0);
unsigned int consumed = 0;
/* At the moment, we dont care for the version. This might change
* in the future, but for now, we just discard it. */
plaintext = (determine_json_version(buffer, buffer_len, &consumed) == -1);
if (plaintext) {
/* In case of plaintext, we just add a single block and change its
* full_text pointer later. */
struct status_block *new_block = scalloc(sizeof(struct status_block));
TAILQ_INSERT_TAIL(&statusline_head, new_block, blocks);
} else {
/* At the moment, we dont care for the version. This might change
* in the future, but for now, we just discard it. */
while (*json_input != '\n' && *json_input != '\0') {
json_input++;
rec--;
}
json_input += consumed;
rec -= consumed;
}
first_line = false;
}

View File

@ -0,0 +1,104 @@
/*
* vim:ts=4:sw=4:expandtab
*
* i3bar - an xcb-based status- and ws-bar for i3
* © 2010-2012 Axel Wagner and contributors (see also: LICENSE)
*
* determine_json_version.c: Determines the JSON protocol version based on the
* first line of input from a child program.
*
*/
#include <stdlib.h>
#include <unistd.h>
#include <sys/types.h>
#include <sys/wait.h>
#include <signal.h>
#include <stdio.h>
#include <fcntl.h>
#include <string.h>
#include <errno.h>
#include <err.h>
#include <ev.h>
#include <stdbool.h>
#include <stdint.h>
#include <yajl/yajl_common.h>
#include <yajl/yajl_parse.h>
#include <yajl/yajl_version.h>
static bool version_key;
static int32_t version_number;
#if YAJL_MAJOR >= 2
static int version_integer(void *ctx, long long val) {
#else
static int version_integer(void *ctx, long val) {
#endif
if (version_key)
version_number = (uint32_t)val;
return 1;
}
#if YAJL_MAJOR >= 2
static int version_map_key(void *ctx, const unsigned char *stringval, size_t stringlen) {
#else
static int version_map_key(void *ctx, const unsigned char *stringval, unsigned int stringlen) {
#endif
version_key = (stringlen == strlen("version") &&
strncmp((const char*)stringval, "version", strlen("version")) == 0);
return 1;
}
static yajl_callbacks version_callbacks = {
NULL, /* null */
NULL, /* boolean */
&version_integer,
NULL, /* double */
NULL, /* number */
NULL, /* string */
NULL, /* start_map */
&version_map_key,
NULL, /* end_map */
NULL, /* start_array */
NULL /* end_array */
};
/*
* Determines the JSON i3bar protocol version from the given buffer. In case
* the buffer does not contain valid JSON, or no version field is found, this
* function returns -1. The amount of bytes consumed by parsing the header is
* returned in *consumed (if non-NULL).
*
* The return type is an int32_t to avoid machines with different sizes of
* 'int' to allow different values here. Its highly unlikely we ever exceed
* even an int8_t, but still
*
*/
int32_t determine_json_version(const unsigned char *buffer, int length, unsigned int *consumed) {
#if YAJL_MAJOR >= 2
yajl_handle handle = yajl_alloc(&version_callbacks, NULL, NULL);
/* Allow trailing garbage. yajl 1 always behaves that way anyways, but for
* yajl 2, we need to be explicit. */
yajl_config(handle, yajl_allow_trailing_garbage, 1);
#else
yajl_parser_config parse_conf = { 0, 0 };
yajl_handle handle = yajl_alloc(&version_callbacks, &parse_conf, NULL, NULL);
#endif
version_key = false;
version_number = -1;
yajl_status state = yajl_parse(handle, buffer, length);
if (state != yajl_status_ok) {
version_number = -1;
if (consumed != NULL)
*consumed = 0;
} else {
if (consumed != NULL)
*consumed = yajl_get_bytes_consumed(handle);
}
yajl_free(handle);
return version_number;
}