1 #ifndef PNGTILE_CTX_H

     2 #define PNGTILE_CTX_H

     3 

     4 /**

     5  * Shared context between images, used to provide a threadpool for parralelizing tile operations

     6  */

     7 #include "pngtile.h"

     8 

     9 #include <pthread.h>

    10 #include <sys/queue.h>

    11 #include <stdbool.h>

    12 

    13 /**

    14  * Worker thread

    15  */

    16 struct pt_thread {

    17     /** Shared context */

    18     struct pt_ctx *ctx;

    19 

    20     /** Thread handle */

    21     pthread_t tid;

    22 

    23     /** @see pt_ctx::threads */

    24     TAILQ_ENTRY(pt_thread) ctx_threads;

    25 };

    26 

    27 /**

    28  * Work function

    29  */

    30 typedef void (*pt_work_func) (void *arg);

    31 

    32 /**

    33  * Work that needs to be done

    34  */

    35 struct pt_work {

    36     /** Work func */

    37     pt_work_func func;

    38 

    39     /** Work info */

    40     void *arg;

    41     

    42     /** @see pt_ctx::work */

    43     TAILQ_ENTRY(pt_work) ctx_work;

    44 };

    45 

    46 /**

    47  * Shared context

    48  */

    49 struct pt_ctx {

    50     /** Accepting new work */

    51     bool running;

    52 

    53     /** Threadpool */

    54     TAILQ_HEAD(pt_ctx_threads, pt_thread) threads;

    55 

    56     /** Pending work */

    57     TAILQ_HEAD(pt_ctx_work, pt_work) work;

    58 

    59     /** Control access to ::work */

    60     pthread_mutex_t work_mutex;

    61 

    62     /** Wait for work to become available */

    63     pthread_cond_t work_cond;

    64 

    65     /** Thread is idle */

    66     pthread_cond_t idle_cond;

    67 };

    68 

    69 /**

    70  * Enqueue a work unit

    71  */

    72 int pt_ctx_work (struct pt_ctx *ctx, pt_work_func func, void *arg);

    73 

    74 

    75 #endif