Merge pull request #402 from progandy/without-fgets

swaybar: read status line without fgets
This commit is contained in:
Drew DeVault 2015-12-24 07:04:35 -07:00
commit deb1546be3

View file

@ -1,3 +1,4 @@
#include <fcntl.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
@ -60,9 +61,9 @@ list_t *status_line = NULL;
list_t *workspaces = NULL;
int socketfd;
pid_t pid;
int pipefd[2];
FILE *command;
int status_read_fd;
char line[1024];
char line_rest[1024];
char *output, *status_command;
struct registry *registry;
struct window *window;
@ -110,10 +111,11 @@ struct {
int bufsize;
char *buffer;
char *line_start;
char *parserpos;
bool escape;
int depth;
int state[I3JSON_MAXDEPTH+1];
} i3json_state = { 0, NULL, NULL, false, 0, { I3JSON_UNKNOWN } };
} i3json_state = { 0, NULL, NULL, NULL, false, 0, { I3JSON_UNKNOWN } };
void swaybar_teardown() {
@ -122,8 +124,8 @@ void swaybar_teardown() {
registry_teardown(registry);
}
if (command) {
fclose(command);
if (status_read_fd) {
close(status_read_fd);
}
if (pid) {
@ -137,8 +139,8 @@ void swaybar_teardown() {
}
}
if (pipefd[0]) {
close(pipefd[0]);
if (status_read_fd) {
close(status_read_fd);
}
}
@ -425,9 +427,9 @@ void render() {
cairo_set_source_u32(window->cairo, colors.separator);
cairo_set_line_width(window->cairo, 1);
cairo_move_to(window->cairo, blockpos + width
+ block->separator_block_width/2, margin);
+ block->separator_block_width/2, margin);
cairo_line_to(window->cairo, blockpos + width
+ block->separator_block_width/2, window->height - margin);
+ block->separator_block_width/2, window->height - margin);
cairo_stroke(window->cairo);
}
}
@ -607,34 +609,124 @@ void parse_json(const char *text) {
json_object_put(results);
}
int i3json_handle(FILE *file) {
char *c;
int handled = 0;
// handle partially buffered data
// make sure 1023+1 bytes at the end are free
if (i3json_state.line_start) {
int len = strlen(i3json_state.line_start);
memmove(i3json_state.buffer, i3json_state.line_start, len+1);
if (i3json_state.bufsize < len+1024) {
i3json_state.bufsize += 1024;
i3json_state.buffer = realloc(i3json_state.buffer, i3json_state.bufsize);
// Read line from file descriptor, only show the line tail if it is too long.
// In non-blocking mode treat "no more data" as a linebreak.
// If data after a line break has been read, return it in rest.
// If rest is non-empty, then use that as the start of the next line.
int read_line_tail(int fd, char *buf, int nbyte, char *rest) {
if (fd < 0 || !buf || !nbyte) {
return -1;
}
int l;
char *buffer = malloc(nbyte*2+1);
char *readpos = buffer;
char *lf;
// prepend old data to new line if necessary
if (rest) {
l = strlen(rest);
if (l > nbyte) {
strcpy(buffer, rest + l - nbyte);
readpos += nbyte;
} else if (l) {
strcpy(buffer, rest);
readpos += l;
}
c = i3json_state.buffer+len;
i3json_state.line_start = i3json_state.buffer;
} else if (!i3json_state.buffer) {
i3json_state.buffer = malloc(1024);
i3json_state.bufsize = 1024;
c = i3json_state.buffer;
}
// read until a linefeed is found or no more data is available
while ((l = read(fd, readpos, nbyte)) > 0) {
readpos[l] = '\0';
lf = strchr(readpos, '\n');
if (lf) {
// linefeed found, replace with \0
*lf = '\0';
// give data from the end of the line, try to fill the buffer
if (lf-buffer > nbyte) {
strcpy(buf, lf - nbyte + 1);
} else {
strcpy(buf, buffer);
}
// we may have read data from the next line, save it to rest
if (rest) {
rest[0] = '\0';
strcpy(rest, lf + 1);
}
free(buffer);
return strlen(buf);
} else {
// no linefeed found, slide data back.
int overflow = readpos - buffer + l - nbyte;
if (overflow > 0) {
memmove(buffer, buffer + overflow , nbyte + 1);
}
}
}
if (l < 0) {
free(buffer);
return l;
}
readpos[l]='\0';
if (rest) {
rest[0] = '\0';
}
if (nbyte < readpos - buffer + l - 1) {
memcpy(buf, readpos - nbyte + l + 1, nbyte);
} else {
c = i3json_state.buffer;
strncpy(buf, buffer, nbyte);
}
buf[nbyte-1] = '\0';
free(buffer);
return strlen(buf);
}
// make sure that enough buffer space is available starting from parserpos
void i3json_ensure_free(int min_free) {
int _step = 10240;
int r = min_free % _step;
if (r) {
min_free += _step - r;
}
if (!i3json_state.buffer) {
i3json_state.buffer = malloc(min_free);
i3json_state.bufsize = min_free;
i3json_state.parserpos = i3json_state.buffer;
} else {
int len = 0;
int pos = 0;
if (i3json_state.line_start) {
len = strlen(i3json_state.line_start);
pos = i3json_state.parserpos - i3json_state.line_start;
if (i3json_state.line_start != i3json_state.buffer) {
memmove(i3json_state.buffer, i3json_state.line_start, len+1);
}
} else {
len = strlen(i3json_state.buffer);
}
if (i3json_state.bufsize < len+min_free) {
i3json_state.bufsize += min_free;
if (i3json_state.bufsize > 1024000) {
sway_abort("Status line json too long or malformed.");
}
i3json_state.buffer = realloc(i3json_state.buffer, i3json_state.bufsize);
if (!i3json_state.buffer) {
sway_abort("Could not allocate json buffer");
}
}
if (i3json_state.line_start) {
i3json_state.line_start = i3json_state.buffer;
i3json_state.parserpos = i3json_state.buffer + pos;
} else {
i3json_state.parserpos = i3json_state.buffer;
}
}
if (!i3json_state.buffer) {
sway_abort("Could not allocate buffer.");
}
// get fresh data at the end of the buffer
if (!fgets(c, 1023, file)) return -1;
c[1023] = '\0';
}
// continue parsing from last parserpos
int i3json_parse() {
char *c = i3json_state.parserpos;
int handled = 0;
while (*c) {
if (i3json_state.state[i3json_state.depth] == I3JSON_STRING) {
if (!i3json_state.escape && *c == '"') {
@ -659,11 +751,11 @@ int i3json_handle(FILE *file) {
}
--i3json_state.depth;
if (i3json_state.depth == 1) {
ssize_t len = c-i3json_state.line_start+1;
char p = c[len];
c[len] = '\0';
// c[1] is valid since c[0] != '\0'
char p = c[1];
c[1] = '\0';
parse_json(i3json_state.line_start);
c[len] = p;
c[1] = p;
++handled;
i3json_state.line_start = c+1;
}
@ -679,9 +771,30 @@ int i3json_handle(FILE *file) {
}
++c;
}
i3json_state.parserpos = c;
return handled;
}
// append data and parse it.
int i3json_handle_data(char *data) {
int len = strlen(data);
i3json_ensure_free(len);
strcpy(i3json_state.parserpos, data);
return i3json_parse();
}
// read data from fd and parse it.
int i3json_handle_fd(int fd) {
i3json_ensure_free(10240);
// get fresh data at the end of the buffer
int readlen = read(fd, i3json_state.parserpos, 10239);
if (readlen < 0) {
return readlen;
}
i3json_state.parserpos[readlen] = '\0';
return i3json_parse();
}
void poll_for_update() {
fd_set readfds;
int activity;
@ -698,7 +811,7 @@ void poll_for_update() {
dirty = false;
FD_ZERO(&readfds);
FD_SET(socketfd, &readfds);
FD_SET(pipefd[0], &readfds);
FD_SET(status_read_fd, &readfds);
activity = select(FD_SETSIZE, &readfds, NULL, NULL, NULL);
if (activity < 0) {
@ -714,41 +827,40 @@ void poll_for_update() {
dirty = true;
}
if (status_command && FD_ISSET(pipefd[0], &readfds)) {
if (status_command && FD_ISSET(status_read_fd, &readfds)) {
sway_log(L_DEBUG, "Got update from status command.");
int linelen;
switch (protocol) {
case I3BAR:
sway_log(L_DEBUG, "Got i3bar protocol.");
if (i3json_handle(command) > 0) {
if (i3json_handle_fd(status_read_fd) > 0) {
dirty = true;
}
break;
case TEXT:
case UNDEF:
sway_log(L_DEBUG, "Got text protocol.");
fgets(line, sizeof(line), command);
linelen = strlen(line) - 1;
if (line[linelen] == '\n') {
line[linelen] = '\0';
read_line_tail(status_read_fd, line, sizeof(line), line_rest);
dirty = true;
break;
case UNDEF:
sway_log(L_DEBUG, "Detecting protocol...");
if (read_line_tail(status_read_fd, line, sizeof(line), line_rest) < 0) {
break;
}
dirty = true;
if (protocol == UNDEF) {
protocol = TEXT;
if (line[0] == '{') {
// detect i3bar json protocol
json_object *proto = json_tokener_parse(line);
json_object *version;
if (proto) {
if (json_object_object_get_ex(proto, "version", &version)
&& json_object_get_int(version) == 1
) {
sway_log(L_DEBUG, "Switched to i3bar protocol.");
protocol = I3BAR;
line[0] = '\0';
}
json_object_put(proto);
protocol = TEXT;
if (line[0] == '{') {
// detect i3bar json protocol
json_object *proto = json_tokener_parse(line);
json_object *version;
if (proto) {
if (json_object_object_get_ex(proto, "version", &version)
&& json_object_get_int(version) == 1
) {
sway_log(L_DEBUG, "Switched to i3bar protocol.");
protocol = I3BAR;
i3json_handle_data(line_rest);
}
json_object_put(proto);
}
}
break;
@ -831,6 +943,7 @@ int main(int argc, char **argv) {
bar_ipc_init(desired_output, bar_id);
if (status_command) {
int pipefd[2];
pipe(pipefd);
pid = fork();
if (pid == 0) {
@ -848,8 +961,8 @@ int main(int argc, char **argv) {
}
close(pipefd[1]);
command = fdopen(pipefd[0], "r");
setbuf(command, NULL);
status_read_fd = pipefd[0];
fcntl(status_read_fd, F_SETFL, O_NONBLOCK);
line[0] = '\0';
}