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mirror of https://github.com/mpv-player/mpv synced 2024-11-18 21:16:10 +01:00
mpv/common/msg.c
wm4 f73778ad82 msg, client API: buffer partial lines
The API could return partial lines, meaning the message could stop
in the middle of a line, and the next message would have the rest of
it (or just the next part of it). This was a pain for the user, so do
the nasty task of buffering the lines ourselves.

Now only complete lines are sent. To make things even easier for the
API user, don't put multiple lines into a single event, but split them.

The terminal output code needed something similar (inserting a prefix
header on start of each line). To avoid code duplication, this commit
refactors the terminal output so that lines are split in a single
place.
2014-10-08 13:11:55 +02:00

626 lines
18 KiB
C

/*
* This file is part of MPlayer.
*
* MPlayer 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.
*
* MPlayer 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 MPlayer; if not, write to the Free Software Foundation, Inc.,
* 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
*/
#include <stdio.h>
#include <stdlib.h>
#include <stdarg.h>
#include <string.h>
#include <unistd.h>
#include <assert.h>
#include <pthread.h>
#include <stdint.h>
#include "talloc.h"
#include "misc/bstr.h"
#include "osdep/atomics.h"
#include "common/common.h"
#include "common/global.h"
#include "misc/ring.h"
#include "options/options.h"
#include "osdep/terminal.h"
#include "osdep/io.h"
#include "osdep/timer.h"
#include "msg.h"
#include "msg_control.h"
/* maximum message length of mp_msg */
#define MSGSIZE_MAX 6144
struct mp_log_root {
struct mpv_global *global;
// --- protected by mp_msg_lock
char *msglevels;
bool use_terminal; // make accesses to stderr/stdout
bool module;
bool show_time;
bool termosd; // use terminal control codes for status line
int blank_lines; // number of lines useable by status
int status_lines; // number of current status lines
bool color;
int verbose;
bool force_stderr;
struct mp_log_buffer **buffers;
int num_buffers;
FILE *stats_file;
// --- semi-atomic access
bool mute;
// --- must be accessed atomically
/* This is incremented every time the msglevels must be reloaded.
* (This is perhaps better than maintaining a globally accessible and
* synchronized mp_log tree.) */
atomic_ulong reload_counter;
// --- protected by mp_msg_lock
char buffer[MSGSIZE_MAX];
};
struct mp_log {
struct mp_log_root *root;
const char *prefix;
const char *verbose_prefix;
int level; // minimum log level for any outputs
int terminal_level; // minimum log level for terminal output
atomic_ulong reload_counter;
};
struct mp_log_buffer {
struct mp_log_root *root;
struct mp_ring *ring;
int level;
void (*wakeup_cb)(void *ctx);
void *wakeup_cb_ctx;
};
// Protects some (not all) state in mp_log_root
static pthread_mutex_t mp_msg_lock = PTHREAD_MUTEX_INITIALIZER;
static const struct mp_log null_log = {0};
struct mp_log *const mp_null_log = (struct mp_log *)&null_log;
static bool match_mod(const char *name, bstr mod)
{
if (bstr_equals0(mod, "all"))
return true;
// Path prefix matches
bstr b = bstr0(name);
return bstr_eatstart(&b, mod) && (bstr_eatstart0(&b, "/") || !b.len);
}
static void update_loglevel(struct mp_log *log)
{
pthread_mutex_lock(&mp_msg_lock);
log->level = -1;
log->terminal_level = -1;
if (log->root->use_terminal) {
log->level = MSGL_STATUS + log->root->verbose; // default log level
bstr s = bstr0(log->root->msglevels);
bstr mod;
int level;
while (mp_msg_split_msglevel(&s, &mod, &level) > 0) {
if (match_mod(log->verbose_prefix, mod))
log->level = level;
}
log->terminal_level = log->root->use_terminal ? log->level : -1;
}
for (int n = 0; n < log->root->num_buffers; n++)
log->level = MPMAX(log->level, log->root->buffers[n]->level);
if (log->root->stats_file)
log->level = MPMAX(log->level, MSGL_STATS);
atomic_store(&log->reload_counter, atomic_load(&log->root->reload_counter));
pthread_mutex_unlock(&mp_msg_lock);
}
// Return whether the message at this verbosity level would be actually printed.
// Thread-safety: see mp_msg().
bool mp_msg_test(struct mp_log *log, int lev)
{
struct mp_log_root *root = log->root;
if (!root || root->mute)
return false;
if (atomic_load(&log->reload_counter) != atomic_load(&root->reload_counter))
update_loglevel(log);
return lev <= log->level;
}
// Reposition cursor and clear lines for outputting the status line. In certain
// cases, like term OSD and subtitle display, the status can consist of
// multiple lines.
static void prepare_status_line(struct mp_log_root *root, char *new_status)
{
FILE *f = stderr;
size_t new_lines = 1;
char *tmp = new_status;
while (1) {
tmp = strchr(tmp, '\n');
if (!tmp)
break;
new_lines++;
tmp++;
}
size_t old_lines = root->status_lines;
size_t clear_lines = MPMIN(MPMAX(new_lines, old_lines), root->blank_lines);
// clear the status line itself
fprintf(f, "\r\033[K");
// and clear all previous old lines
for (size_t n = 1; n < clear_lines; n++)
fprintf(f, "\033[A\r\033[K");
// skip "unused" blank lines, so that status is aligned to term bottom
for (size_t n = new_lines; n < clear_lines; n++)
fprintf(f, "\n");
root->status_lines = new_lines;
root->blank_lines = MPMAX(root->blank_lines, new_lines);
}
static void flush_status_line(struct mp_log_root *root)
{
// If there was a status line, don't overwrite it, but skip it.
if (root->status_lines)
fprintf(stderr, "\n");
root->status_lines = 0;
root->blank_lines = 0;
}
void mp_msg_flush_status_line(struct mpv_global *global)
{
pthread_mutex_lock(&mp_msg_lock);
flush_status_line(global->log->root);
pthread_mutex_unlock(&mp_msg_lock);
}
bool mp_msg_has_status_line(struct mpv_global *global)
{
pthread_mutex_lock(&mp_msg_lock);
bool r = global->log->root->status_lines > 0;
pthread_mutex_unlock(&mp_msg_lock);
return r;
}
static void set_term_color(FILE *stream, int c)
{
if (c == -1) {
fprintf(stream, "\033[0m");
} else {
fprintf(stream, "\033[%d;3%dm", c >> 3, c & 7);
}
}
static void set_msg_color(FILE* stream, int lev)
{
static const int v_colors[] = {9, 1, 3, -1, -1, 2, 8, 8, 8, -1};
set_term_color(stream, v_colors[lev]);
}
static void pretty_print_module(FILE* stream, const char *prefix, bool use_color, int lev)
{
// Use random color based on the name of the module
if (use_color) {
size_t prefix_len = strlen(prefix);
unsigned int mod = 0;
for (int i = 0; i < prefix_len; ++i)
mod = mod * 33 + prefix[i];
set_term_color(stream, (mod + 1) % 15 + 1);
}
fprintf(stream, "%10s", prefix);
if (use_color)
set_term_color(stream, -1);
fprintf(stream, ": ");
if (use_color)
set_msg_color(stream, lev);
}
static bool test_terminal_level(struct mp_log *log, int lev)
{
return lev <= log->terminal_level &&
!(lev == MSGL_STATUS && terminal_in_background());
}
static void print_terminal_line(struct mp_log *log, int lev, char *text)
{
if (!test_terminal_level(log, lev))
return;
struct mp_log_root *root = log->root;
FILE *stream = (root->force_stderr || lev == MSGL_STATUS) ? stderr : stdout;
if (lev != MSGL_STATUS)
flush_status_line(root);
if (root->color)
set_msg_color(stream, lev);
if (root->show_time)
fprintf(stream, "[%" PRId64 "] ", mp_time_us());
const char *prefix = log->prefix;
if ((lev >= MSGL_V) || root->verbose || root->module)
prefix = log->verbose_prefix;
if (prefix) {
if (root->module) {
pretty_print_module(stream, prefix, root->color, lev);
} else {
fprintf(stream, "[%s] ", prefix);
}
}
fprintf(stream, "%s", text);
if (root->color)
set_term_color(stream, -1);
fflush(stream);
}
static void write_msg_to_buffers(struct mp_log *log, int lev, char *text)
{
struct mp_log_root *root = log->root;
for (int n = 0; n < root->num_buffers; n++) {
struct mp_log_buffer *buffer = root->buffers[n];
if (lev <= buffer->level && lev != MSGL_STATUS) {
// Assuming a single writer (serialized by msg lock)
int avail = mp_ring_available(buffer->ring) / sizeof(void *);
if (avail < 1)
continue;
struct mp_log_buffer_entry *entry = talloc_ptrtype(NULL, entry);
if (avail > 1) {
*entry = (struct mp_log_buffer_entry) {
.prefix = talloc_strdup(entry, log->verbose_prefix),
.level = lev,
.text = talloc_strdup(entry, text),
};
} else {
// write overflow message to signal that messages might be lost
*entry = (struct mp_log_buffer_entry) {
.prefix = "overflow",
.level = MSGL_FATAL,
.text = "log message buffer overflow\n",
};
}
mp_ring_write(buffer->ring, (unsigned char *)&entry, sizeof(entry));
if (buffer->wakeup_cb)
buffer->wakeup_cb(buffer->wakeup_cb_ctx);
}
}
}
static void dump_stats(struct mp_log *log, int lev, char *text)
{
struct mp_log_root *root = log->root;
if (lev == MSGL_STATS && root->stats_file) {
fprintf(root->stats_file, "%"PRId64" %s #%s\n", mp_time_us(), text,
log->verbose_prefix);
}
}
void mp_msg_va(struct mp_log *log, int lev, const char *format, va_list va)
{
if (!mp_msg_test(log, lev))
return; // do not display
pthread_mutex_lock(&mp_msg_lock);
char tmp[MSGSIZE_MAX];
bool use_tmp = lev == MSGL_STATUS || lev == MSGL_STATS;
struct mp_log_root *root = log->root;
char *text = use_tmp ? tmp : root->buffer;
int len = use_tmp ? 0 : strlen(text);
if (vsnprintf(text + len, MSGSIZE_MAX - len, format, va) < 0)
snprintf(text + len, MSGSIZE_MAX - len, "[fprintf error]\n");
text[MSGSIZE_MAX - 2] = '\n';
text[MSGSIZE_MAX - 1] = 0;
if (lev == MSGL_STATS) {
dump_stats(log, lev, text);
} else if (lev == MSGL_STATUS && !test_terminal_level(log, lev)) {
/* discard */
} else {
if (lev == MSGL_STATUS && root->termosd)
prepare_status_line(root, text);
// Split away each line. Normally we require full lines; buffer partial
// lines if they happen.
while (1) {
char *end = strchr(text, '\n');
if (!end)
break;
char *next = &end[1];
char saved = next[0];
next[0] = '\0';
print_terminal_line(log, lev, text);
write_msg_to_buffers(log, lev, text);
next[0] = saved;
text = next;
}
if (lev == MSGL_STATUS) {
if (text[0]) {
len = strlen(text);
if (len < MSGSIZE_MAX - 1) {
text[len] = root->termosd ? '\r' : '\n';
text[len + 1] = '\0';
}
print_terminal_line(log, lev, text);
}
root->buffer[0] = '\0';
} else {
int leftover = strlen(text);
memmove(root->buffer, text, leftover + 1);
}
}
pthread_mutex_unlock(&mp_msg_lock);
}
// Create a new log context, which uses talloc_ctx as talloc parent, and parent
// as logical parent.
// The name is the prefix put before the output. It's usually prefixed by the
// parent's name. If the name starts with "/", the parent's name is not
// prefixed (except in verbose mode), and if it starts with "!", the name is
// not printed at all (except in verbose mode).
// If name is NULL, the parent's name/prefix is used.
// Thread-safety: fully thread-safe, but keep in mind that talloc is not (so
// talloc_ctx must be owned by the current thread).
struct mp_log *mp_log_new(void *talloc_ctx, struct mp_log *parent,
const char *name)
{
assert(parent);
struct mp_log *log = talloc_zero(talloc_ctx, struct mp_log);
if (!parent->root)
return log; // same as null_log
log->root = parent->root;
if (name) {
if (name[0] == '!') {
name = &name[1];
} else if (name[0] == '/') {
name = &name[1];
log->prefix = talloc_strdup(log, name);
} else {
log->prefix = parent->prefix
? talloc_asprintf(log, "%s/%s", parent->prefix, name)
: talloc_strdup(log, name);
}
log->verbose_prefix = parent->prefix
? talloc_asprintf(log, "%s/%s", parent->prefix, name)
: talloc_strdup(log, name);
if (log->prefix && !log->prefix[0])
log->prefix = NULL;
if (!log->verbose_prefix[0])
log->verbose_prefix = "global";
} else {
log->prefix = talloc_strdup(log, parent->prefix);
log->verbose_prefix = talloc_strdup(log, parent->verbose_prefix);
}
return log;
}
void mp_msg_init(struct mpv_global *global)
{
assert(!global->log);
struct mp_log_root *root = talloc_zero(NULL, struct mp_log_root);
*root = (struct mp_log_root){
.global = global,
.reload_counter = ATOMIC_VAR_INIT(1),
};
struct mp_log dummy = { .root = root };
struct mp_log *log = mp_log_new(root, &dummy, "");
global->log = log;
mp_msg_update_msglevels(global);
}
void mp_msg_update_msglevels(struct mpv_global *global)
{
struct mp_log_root *root = global->log->root;
struct MPOpts *opts = global->opts;
if (!opts)
return;
pthread_mutex_lock(&mp_msg_lock);
root->verbose = opts->verbose;
root->module = opts->msg_module;
root->use_terminal = opts->use_terminal;
root->show_time = opts->msg_time;
if (root->use_terminal) {
root->color = opts->msg_color && isatty(STDOUT_FILENO);
root->termosd = isatty(STDERR_FILENO);
}
talloc_free(root->msglevels);
root->msglevels = talloc_strdup(root, global->opts->msglevels);
atomic_fetch_add(&root->reload_counter, 1);
pthread_mutex_unlock(&mp_msg_lock);
}
void mp_msg_mute(struct mpv_global *global, bool mute)
{
struct mp_log_root *root = global->log->root;
root->mute = mute;
}
void mp_msg_force_stderr(struct mpv_global *global, bool force_stderr)
{
struct mp_log_root *root = global->log->root;
root->force_stderr = force_stderr;
}
void mp_msg_uninit(struct mpv_global *global)
{
struct mp_log_root *root = global->log->root;
if (root->stats_file)
fclose(root->stats_file);
talloc_free(root);
global->log = NULL;
}
struct mp_log_buffer *mp_msg_log_buffer_new(struct mpv_global *global,
int size, int level,
void (*wakeup_cb)(void *ctx),
void *wakeup_cb_ctx)
{
struct mp_log_root *root = global->log->root;
#if !HAVE_ATOMICS
return NULL;
#endif
pthread_mutex_lock(&mp_msg_lock);
struct mp_log_buffer *buffer = talloc_ptrtype(NULL, buffer);
*buffer = (struct mp_log_buffer) {
.root = root,
.level = level,
.ring = mp_ring_new(buffer, sizeof(void *) * size),
.wakeup_cb = wakeup_cb,
.wakeup_cb_ctx = wakeup_cb_ctx,
};
if (!buffer->ring)
abort();
MP_TARRAY_APPEND(root, root->buffers, root->num_buffers, buffer);
atomic_fetch_add(&root->reload_counter, 1);
pthread_mutex_unlock(&mp_msg_lock);
return buffer;
}
void mp_msg_log_buffer_destroy(struct mp_log_buffer *buffer)
{
if (!buffer)
return;
pthread_mutex_lock(&mp_msg_lock);
struct mp_log_root *root = buffer->root;
for (int n = 0; n < root->num_buffers; n++) {
if (root->buffers[n] == buffer) {
MP_TARRAY_REMOVE_AT(root->buffers, root->num_buffers, n);
goto found;
}
}
abort();
found:
while (1) {
struct mp_log_buffer_entry *e = mp_msg_log_buffer_read(buffer);
if (!e)
break;
talloc_free(e);
}
talloc_free(buffer);
atomic_fetch_add(&root->reload_counter, 1);
pthread_mutex_unlock(&mp_msg_lock);
}
// Return a queued message, or if the buffer is empty, NULL.
// Thread-safety: one buffer can be read by a single thread only.
struct mp_log_buffer_entry *mp_msg_log_buffer_read(struct mp_log_buffer *buffer)
{
void *ptr = NULL;
int read = mp_ring_read(buffer->ring, (unsigned char *)&ptr, sizeof(ptr));
if (read == 0)
return NULL;
if (read != sizeof(ptr))
abort();
return ptr;
}
int mp_msg_open_stats_file(struct mpv_global *global, const char *path)
{
struct mp_log_root *root = global->log->root;
int r;
pthread_mutex_lock(&mp_msg_lock);
if (root->stats_file)
fclose(root->stats_file);
root->stats_file = fopen(path, "wb");
r = root->stats_file ? 0 : -1;
pthread_mutex_unlock(&mp_msg_lock);
mp_msg_update_msglevels(global);
return r;
}
// Thread-safety: fully thread-safe, but keep in mind that the lifetime of
// log must be guaranteed during the call.
// Never call this from signal handlers.
void mp_msg(struct mp_log *log, int lev, const char *format, ...)
{
va_list va;
va_start(va, format);
mp_msg_va(log, lev, format, va);
va_end(va);
}
const char *const mp_log_levels[MSGL_MAX + 1] = {
[MSGL_FATAL] = "fatal",
[MSGL_ERR] = "error",
[MSGL_WARN] = "warn",
[MSGL_INFO] = "info",
[MSGL_STATUS] = "status",
[MSGL_V] = "v",
[MSGL_DEBUG] = "debug",
[MSGL_TRACE] = "trace",
[MSGL_STATS] = "stats",
};
int mp_msg_split_msglevel(struct bstr *s, struct bstr *out_mod, int *out_level)
{
if (s->len == 0)
return 0;
bstr elem, rest;
bstr_split_tok(*s, ":", &elem, &rest);
bstr mod, level;
if (!bstr_split_tok(elem, "=", &mod, &level) || mod.len == 0)
return -1;
int ilevel = -1;
for (int n = 0; n < MP_ARRAY_SIZE(mp_log_levels); n++) {
if (mp_log_levels[n] && bstr_equals0(level, mp_log_levels[n])) {
ilevel = n;
break;
}
}
if (ilevel < 0 && !bstr_equals0(level, "no"))
return -1;
*s = rest;
*out_mod = mod;
*out_level = ilevel;
return 1;
}