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#ifndef PNGTILE_CTX_H

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#define PNGTILE_CTX_H

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/**

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

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 */

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#include "pngtile.h"

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#include <pthread.h>

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#include <sys/queue.h>

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#include <stdbool.h>

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/**

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 * Worker thread

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 */

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struct pt_thread {

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    /** Shared context */

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    struct pt_ctx *ctx;

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    /** Thread handle */

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    pthread_t tid;

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    /** @see pt_ctx::threads */

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    TAILQ_ENTRY(pt_thread) ctx_threads;

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};

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/**

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 * Work function

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 */

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

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/**

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 * Work that needs to be done

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 */

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struct pt_work {

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    /** Work func */

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    pt_work_func func;

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    /** Work info */

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    void *arg;

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    /** @see pt_ctx::work */

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    TAILQ_ENTRY(pt_work) ctx_work;

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};

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/**

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 * Shared context

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 */

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struct pt_ctx {

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    /** Accepting new work */

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    bool running;

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    /** Threadpool */

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    TAILQ_HEAD(pt_ctx_threads, pt_thread) threads;

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    /** Pending work */

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    TAILQ_HEAD(pt_ctx_work, pt_work) work;

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    /** Control access to ::work */

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    pthread_mutex_t work_mutex;

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    /** Wait for work to become available */

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    pthread_cond_t work_cond;

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    /** Thread is idle */

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    pthread_cond_t idle_cond;

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};

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/**

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 * Enqueue a work unit

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 */

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

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#endif