/*
* bg.c
*
* Wrapper over pthread with the addition of some interthread comms.
*
* History:
* 20250904 Creation from imgmover prototype.
*
* Author: Dario Rodriguez dario@darionomono.com
* (c) Dario Rodriguez 2025
* This program is licensed under the terms of GNU GPL v2.1+
*/
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <string.h>
#include <pthread.h>
#if !defined(__linux__) && !defined(ANDROID)
#include "win32_pipe.h"
#endif
#include "raylib.h"
#include "rayui.h"
#include "bg.h"
#define UNLOADTIMEOUTSECONDS 10
static int mypipe(int fds[2]);
static int mypiperead(int fd, char *buf, int count);
static int mypipewrite(int fd, char *buf, int count);
void
bg_staticinit(void)
{
#if !defined(__linux__) && !defined(ANDROID)
win32pipe_init();
#endif
}
void
bg_staticfini(void)
{
#if !defined(__linux__) && !defined(ANDROID)
win32pipe_fini();
#endif
}
bg_t *
bg_init(int sizebgload)
{
bg_t *bg;
char *errstr;
bg=NULL;
if((errstr="Insuf. mem. for bg")==NULL
|| (bg=calloc(1,sizeof(bg_t)))==NULL
|| (errstr="Error init pipes (please check program is not blocked in firewall)")==NULL
|| (bg->pipe[0]=bg->pipe[1]=-1)!=-1
|| mypipe(bg->pipe)!=0
|| (errstr="Insuf mem bgload")==NULL
|| (bg->bgload=calloc(sizebgload,sizeof(bgload_t)))==NULL
|| (bg->sizebgload=sizebgload)!=sizebgload
|| (errstr="pthread attr init error")==NULL
|| pthread_attr_init(&(bg->tattr))!=0
|| (errstr="pthread create error")==NULL
|| pthread_create(&(bg->thread),&(bg->tattr),bg_thread,(void *)bg)!=0
|| (bg->flag_threadstarted=1)!=1
) {
global_messagebox("%s",errstr);
bg_free(bg);
return(NULL);
}
return(bg);
}
void
bg_free(bg_t *bg)
{
int i;
if(bg==NULL)
return; /* nothing to do */
if(bg->flag_threadstarted) {
char dummy=1;
#if 1
fprintf(stderr,"bg_free: notifying thread to exit\n");
#endif
mypipewrite(bg->pipe[WR],&dummy,1);
#if 1
fprintf(stderr,"bg_free: joining thread\n");
#endif
pthread_join(bg->thread,NULL);
#if 1
fprintf(stderr,"bg_free: thread joined OK\n");
#endif
bg->flag_threadstarted=0;
}
if(bg->pipe[0]!=-1)
close(bg->pipe[0]),bg->pipe[0]=-1;
if(bg->pipe[1]!=-1)
close(bg->pipe[1]),bg->pipe[1]=-1;
if(bg->bgload!=NULL) {
bgload_t *bgload;
for(i=0,bgload=bg->bgload;i<bg->sizebgload;i++,bgload++) {
if(bgload->has_data) {
UnloadImage(bgload->image);
bgload->has_data=0;
}
}
free(bg->bgload),bg->bgload=NULL,bg->sizebgload=0;
}
return;
}
int
bg_resetmarks(bg_t *bg)
{
int i;
bgload_t *bgload;
if(bg==NULL)
return(-1);
for(i=0,bgload=bg->bgload;i<bg->sizebgload;i++,bgload++)
bgload->has_mark=0;
return(0);
}
bgload_t *
bg_get(bg_t *bg, char *path)
{
int i;
bgload_t *bgload;
if(bg==NULL)
return(NULL);
for(i=0,bgload=bg->bgload;i<bg->sizebgload;i++,bgload++) {
if(bgload->thread_finished && bgload->has_data && strcmp(path,bgload->path)==0) {
bgload->has_mark=1;
#if 1
fprintf(stderr,"bg_get: \"%s\"\n",bgload->path);
#endif
return(bgload);
}
}
return(NULL);
}
int
bg_add(bg_t *bg, char *path)
{
int i;
bgload_t *bgload;
char dummy;
if(bg==NULL)
return(-1);
for(i=0,bgload=bg->bgload;i<bg->sizebgload;i++,bgload++) {
if(bgload->lended_to_thread && strcmp(path,bgload->path)==0) {
bgload->is_todo=1;
bgload->has_mark=1;
gettimeofday(&(bgload->tv_lastadded),NULL); // Breaks premise of "don't touch until thread finished", but this is rather innocuous
dummy=0;
mypipewrite(bg->pipe[WR],&dummy,1);
return(0); /* already on list */
}
}
for(i=0,bgload=bg->bgload;i<bg->sizebgload;i++,bgload++) {
if(bgload->lended_to_thread==0) {
memset(bgload,0,sizeof(bgload_t));
strncpy(bgload->path,path,sizeof(bgload->path));
bgload->path[sizeof(bgload->path)-1]='\0';
bgload->is_todo=1;
bgload->has_mark=1;
gettimeofday(&(bgload->tv_lastadded),NULL); // Breaks premise of "don't touch until thread finished", but this is rather innocuous
dummy=0;
bgload->lended_to_thread=1;
mypipewrite(bg->pipe[WR],&dummy,1);
return(0); /* added to list */
}
}
return(-1); /* couldn't add */
}
int
bg_freeunmarked(bg_t *bg)
{
int i;
bgload_t *bgload;
time_t now;
if(bg==NULL)
return(-1);
now=time(NULL);
for(i=0,bgload=bg->bgload;i<bg->sizebgload;i++,bgload++) {
if(bgload->lended_to_thread && bgload->thread_finished && bgload->has_mark==0) {
if(bgload->has_data && (bgload->lastused<(now-UNLOADTIMEOUTSECONDS) || bgload->lastused>(now+UNLOADTIMEOUTSECONDS))) {
#if 1
fprintf(stderr,"bg: Unloading: \"%s\"\n",bgload->path);
#endif
UnloadImage(bgload->image);
bgload->has_data=0;
}
#if 1
else {
fprintf(stderr,"bg: Cancelling: \"%s\"\n",bgload->path);
}
#endif
memset(bgload,0,sizeof(bgload_t));
} else if(bgload->lended_to_thread && bgload->thread_finished && bgload->has_mark!=0 && bgload->has_data) {
bgload->lastused=now;
}
}
return(0);
}
void *
bg_thread(void *parambg)
{
bg_t *bg;
char dummy;
bg=(bg_t *)parambg;
int i;
bgload_t *bgload,*candidate;
while(1) {
mypiperead(bg->pipe[RD],&dummy,1);
#if 1
fprintf(stderr,"Thread received byte: %i\n",(int)((unsigned char)dummy));
#endif
if(dummy!=0)
break; /* was told to exit */
for(candidate=NULL,i=0,bgload=bg->bgload;i<bg->sizebgload;i++,bgload++) {
if(bgload->lended_to_thread==0)
continue;
if(bgload->is_todo==0) {
bgload->thread_finished=1;
continue;
}
if(bgload->has_data==0 && bgload->has_failedload==0) {
if(candidate==NULL
|| bgload->tv_lastadded.tv_sec>candidate->tv_lastadded.tv_sec
|| (bgload->tv_lastadded.tv_sec==candidate->tv_lastadded.tv_sec && bgload->tv_lastadded.tv_usec>candidate->tv_lastadded.tv_usec)
) {
candidate=bgload;
}
}
}
if(candidate!=NULL) {
bgload=candidate;
bgload->image=global_loadimage(bgload->path);
if(IsImageValid(bgload->image))
bgload->has_data=1;
else
bgload->has_failedload=1;
bgload->lastused=time(NULL);
bgload->thread_finished=1;
}
}
pthread_exit(NULL);
return(NULL);
}
#if !defined(__linux__) && !defined(ANDROID)
static int
mypipe(int fds[2])
{
return(win32pipe_pipe(fds));
}
static int
mypiperead(int fd, char *buf, int count)
{
return(win32pipe_read(fd,buf,count));
}
static int
mypipewrite(int fd, char *buf, int count)
{
return(win32pipe_write(fd,buf,count));
}
#else
static int
mypipe(int fds[2])
{
return(pipe(fds));
}
static int
mypiperead(int fd, char *buf, int count)
{
return(read(fd,buf,count));
}
static int
mypipewrite(int fd, char *buf, int count)
{
return(write(fd,buf,count));
}
#endif