/*
 * jcapimin.c
 *
 * This file was part of the Independent JPEG Group's software:
 * Copyright (C) 1994-1998, Thomas G. Lane.
 * Modified 2003-2010 by Guido Vollbeding.
 * It was modified by The libjpeg-turbo Project to include only code relevant
 * to libjpeg-turbo.
 * For conditions of distribution and use, see the accompanying README.ijg
 * file.
 *
 * This file contains application interface code for the compression half
 * of the JPEG library.  These are the "minimum" API routines that may be
 * needed in either the normal full-compression case or the transcoding-only
 * case.
 *
 * Most of the routines intended to be called directly by an application
 * are in this file or in jcapistd.c.  But also see jcparam.c for
 * parameter-setup helper routines, jcomapi.c for routines shared by
 * compression and decompression, and jctrans.c for the transcoding case.
 */

#define JPEG_INTERNALS

#include "jinclude.h"
#include "jpeglib.h"


/*
 * Initialization of a JPEG compression object.
 * The error manager must already be set up (in case memory manager fails).
 */

GLOBAL(void)
jpeg_CreateCompress(j_compress_ptr cinfo, int version, size_t structsize) {
	int i;

	/* Guard against version mismatches between library and caller. */
	cinfo->mem = NULL;            /* so jpeg_destroy knows mem mgr not called */
	if (version != JPEG_LIB_VERSION)
		ERREXIT2(cinfo, JERR_BAD_LIB_VERSION, JPEG_LIB_VERSION, version);
	if (structsize != sizeof(struct jpeg_compress_struct))
		ERREXIT2(cinfo, JERR_BAD_STRUCT_SIZE,
		         (int) sizeof(struct jpeg_compress_struct), (int) structsize);

	/* For debugging purposes, we zero the whole master structure.
	 * But the application has already set the err pointer, and may have set
	 * client_data, so we have to save and restore those fields.
	 * Note: if application hasn't set client_data, tools like Purify may
	 * complain here.
	 */
	{
		struct jpeg_error_mgr *err = cinfo->err;
		void *client_data = cinfo->client_data; /* ignore Purify complaint here */
		MEMZERO(cinfo, sizeof(struct jpeg_compress_struct));
		cinfo->err = err;
		cinfo->client_data = client_data;
	}
	cinfo->is_decompressor = FALSE;

	/* Initialize a memory manager instance for this object */
	jinit_memory_mgr((j_common_ptr) cinfo);

	/* Zero out pointers to permanent structures. */
	cinfo->progress = NULL;
	cinfo->dest = NULL;

	cinfo->comp_info = NULL;

	for (i = 0; i < NUM_QUANT_TBLS; i++) {
		cinfo->quant_tbl_ptrs[i] = NULL;
#if JPEG_LIB_VERSION >= 70
		cinfo->q_scale_factor[i] = 100;
#endif
	}

	for (i = 0; i < NUM_HUFF_TBLS; i++) {
		cinfo->dc_huff_tbl_ptrs[i] = NULL;
		cinfo->ac_huff_tbl_ptrs[i] = NULL;
	}

#if JPEG_LIB_VERSION >= 80
	/* Must do it here for emit_dqt in case jpeg_write_tables is used */
	cinfo->block_size = DCTSIZE;
	cinfo->natural_order = jpeg_natural_order;
	cinfo->lim_Se = DCTSIZE2-1;
#endif

	cinfo->script_space = NULL;

	cinfo->input_gamma = 1.0;     /* in case application forgets */

	/* OK, I'm ready */
	cinfo->global_state = CSTATE_START;
}


/*
 * Destruction of a JPEG compression object
 */

GLOBAL(void)
jpeg_destroy_compress(j_compress_ptr cinfo) {
	jpeg_destroy((j_common_ptr) cinfo); /* use common routine */
}


/*
 * Abort processing of a JPEG compression operation,
 * but don't destroy the object itself.
 */

GLOBAL(void)
jpeg_abort_compress(j_compress_ptr cinfo) {
	jpeg_abort((j_common_ptr) cinfo); /* use common routine */
}


/*
 * Forcibly suppress or un-suppress all quantization and Huffman tables.
 * Marks all currently defined tables as already written (if suppress)
 * or not written (if !suppress).  This will control whether they get emitted
 * by a subsequent jpeg_start_compress call.
 *
 * This routine is exported for use by applications that want to produce
 * abbreviated JPEG datastreams.  It logically belongs in jcparam.c, but
 * since it is called by jpeg_start_compress, we put it here --- otherwise
 * jcparam.o would be linked whether the application used it or not.
 */

GLOBAL(void)
jpeg_suppress_tables(j_compress_ptr cinfo, boolean suppress) {
	int i;
	JQUANT_TBL *qtbl;
	JHUFF_TBL *htbl;

	for (i = 0; i < NUM_QUANT_TBLS; i++) {
		if ((qtbl = cinfo->quant_tbl_ptrs[i]) != NULL)
			qtbl->sent_table = suppress;
	}

	for (i = 0; i < NUM_HUFF_TBLS; i++) {
		if ((htbl = cinfo->dc_huff_tbl_ptrs[i]) != NULL)
			htbl->sent_table = suppress;
		if ((htbl = cinfo->ac_huff_tbl_ptrs[i]) != NULL)
			htbl->sent_table = suppress;
	}
}


/*
 * Finish JPEG compression.
 *
 * If a multipass operating mode was selected, this may do a great deal of
 * work including most of the actual output.
 */

GLOBAL(void)
jpeg_finish_compress(j_compress_ptr cinfo) {
	JDIMENSION iMCU_row;

	if (cinfo->global_state == CSTATE_SCANNING ||
	    cinfo->global_state == CSTATE_RAW_OK) {
		/* Terminate first pass */
		if (cinfo->next_scanline < cinfo->image_height)
			ERREXIT(cinfo, JERR_TOO_LITTLE_DATA);
		(*cinfo->master->finish_pass)(cinfo);
	} else if (cinfo->global_state != CSTATE_WRCOEFS)
		ERREXIT1(cinfo, JERR_BAD_STATE, cinfo->global_state);
	/* Perform any remaining passes */
	while (!cinfo->master->is_last_pass) {
		(*cinfo->master->prepare_for_pass)(cinfo);
		for (iMCU_row = 0; iMCU_row < cinfo->total_iMCU_rows; iMCU_row++) {
			if (cinfo->progress != NULL) {
				cinfo->progress->pass_counter = (long) iMCU_row;
				cinfo->progress->pass_limit = (long) cinfo->total_iMCU_rows;
				(*cinfo->progress->progress_monitor)((j_common_ptr) cinfo);
			}
			/* We bypass the main controller and invoke coef controller directly;
			 * all work is being done from the coefficient buffer.
			 */
			if (!(*cinfo->coef->compress_data)(cinfo, (JSAMPIMAGE) NULL))
				ERREXIT(cinfo, JERR_CANT_SUSPEND);
		}
		(*cinfo->master->finish_pass)(cinfo);
	}
	/* Write EOI, do final cleanup */
	(*cinfo->marker->write_file_trailer)(cinfo);
	(*cinfo->dest->term_destination)(cinfo);
	/* We can use jpeg_abort to release memory and reset global_state */
	jpeg_abort((j_common_ptr) cinfo);
}


/*
 * Write a special marker.
 * This is only recommended for writing COM or APPn markers.
 * Must be called after jpeg_start_compress() and before
 * first call to jpeg_write_scanlines() or jpeg_write_raw_data().
 */

GLOBAL(void)
jpeg_write_marker(j_compress_ptr cinfo, int marker,
                  const JOCTET *dataptr, unsigned int datalen) {
	void (*write_marker_byte)(j_compress_ptr info, int val);

	if (cinfo->next_scanline != 0 ||
	    (cinfo->global_state != CSTATE_SCANNING &&
	     cinfo->global_state != CSTATE_RAW_OK &&
	     cinfo->global_state != CSTATE_WRCOEFS))
		ERREXIT1(cinfo, JERR_BAD_STATE, cinfo->global_state);

	(*cinfo->marker->write_marker_header)(cinfo, marker, datalen);
	write_marker_byte = cinfo->marker->write_marker_byte; /* copy for speed */
	while (datalen--) {
		(*write_marker_byte)(cinfo, *dataptr);
		dataptr++;
	}
}

/* Same, but piecemeal. */

GLOBAL(void)
jpeg_write_m_header(j_compress_ptr cinfo, int marker, unsigned int datalen) {
	if (cinfo->next_scanline != 0 ||
	    (cinfo->global_state != CSTATE_SCANNING &&
	     cinfo->global_state != CSTATE_RAW_OK &&
	     cinfo->global_state != CSTATE_WRCOEFS))
		ERREXIT1(cinfo, JERR_BAD_STATE, cinfo->global_state);

	(*cinfo->marker->write_marker_header)(cinfo, marker, datalen);
}

GLOBAL(void)
jpeg_write_m_byte(j_compress_ptr cinfo, int val) {
	(*cinfo->marker->write_marker_byte)(cinfo, val);
}


/*
 * Alternate compression function: just write an abbreviated table file.
 * Before calling this, all parameters and a data destination must be set up.
 *
 * To produce a pair of files containing abbreviated tables and abbreviated
 * image data, one would proceed as follows:
 *
 *              initialize JPEG object
 *              set JPEG parameters
 *              set destination to table file
 *              jpeg_write_tables(cinfo);
 *              set destination to image file
 *              jpeg_start_compress(cinfo, FALSE);
 *              write data...
 *              jpeg_finish_compress(cinfo);
 *
 * jpeg_write_tables has the side effect of marking all tables written
 * (same as jpeg_suppress_tables(..., TRUE)).  Thus a subsequent start_compress
 * will not re-emit the tables unless it is passed write_all_tables=TRUE.
 */

GLOBAL(void)
jpeg_write_tables(j_compress_ptr cinfo) {
	if (cinfo->global_state != CSTATE_START)
		ERREXIT1(cinfo, JERR_BAD_STATE, cinfo->global_state);

	/* (Re)initialize error mgr and destination modules */
	(*cinfo->err->reset_error_mgr)((j_common_ptr) cinfo);
	(*cinfo->dest->init_destination)(cinfo);
	/* Initialize the marker writer ... bit of a crock to do it here. */
	jinit_marker_writer(cinfo);
	/* Write them tables! */
	(*cinfo->marker->write_tables_only)(cinfo);
	/* And clean up. */
	(*cinfo->dest->term_destination)(cinfo);
	/*
	 * In library releases up through v6a, we called jpeg_abort() here to free
	 * any working memory allocated by the destination manager and marker
	 * writer.  Some applications had a problem with that: they allocated space
	 * of their own from the library memory manager, and didn't want it to go
	 * away during write_tables.  So now we do nothing.  This will cause a
	 * memory leak if an app calls write_tables repeatedly without doing a full
	 * compression cycle or otherwise resetting the JPEG object.  However, that
	 * seems less bad than unexpectedly freeing memory in the normal case.
	 * An app that prefers the old behavior can call jpeg_abort for itself after
	 * each call to jpeg_write_tables().
	 */
}
