libjpeg update

git-svn-id: http://svn.miranda-ng.org/main/trunk@5843 1316c22d-e87f-b044-9b9b-93d7a3e3ba9c

1 files changed, 396 insertions, 396 deletions

diff --git a/plugins/AdvaImg/src/LibJPEG/jdapimin.c b/plugins/AdvaImg/src/LibJPEG/jdapimin.c
index 7f1ce4c05b..65f8a491bd 100644
--- a/plugins/AdvaImg/src/LibJPEG/jdapimin.c
+++ b/plugins/AdvaImg/src/LibJPEG/jdapimin.c
@@ -1,396 +1,396 @@
-/*
- * jdapimin.c
- *
- * Copyright (C) 1994-1998, Thomas G. Lane.
- * Modified 2009 by Guido Vollbeding.
- * This file is part of the Independent JPEG Group's software.
- * For conditions of distribution and use, see the accompanying README file.
- *
- * This file contains application interface code for the decompression half
- * of the JPEG library.  These are the "minimum" API routines that may be
- * needed in either the normal full-decompression case or the
- * transcoding-only case.
- *
- * Most of the routines intended to be called directly by an application
- * are in this file or in jdapistd.c.  But also see jcomapi.c for routines
- * shared by compression and decompression, and jdtrans.c for the transcoding
- * case.
- */
-
-#define JPEG_INTERNALS
-#include "jinclude.h"
-#include "jpeglib.h"
-
-
-/*
- * Initialization of a JPEG decompression object.
- * The error manager must already be set up (in case memory manager fails).
- */
-
-GLOBAL(void)
-jpeg_CreateDecompress (j_decompress_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_decompress_struct))
-    ERREXIT2(cinfo, JERR_BAD_STRUCT_SIZE, 
-	     (int) SIZEOF(struct jpeg_decompress_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_decompress_struct));
-    cinfo->err = err;
-    cinfo->client_data = client_data;
-  }
-  cinfo->is_decompressor = TRUE;
-
-  /* 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->src = NULL;
-
-  for (i = 0; i < NUM_QUANT_TBLS; i++)
-    cinfo->quant_tbl_ptrs[i] = NULL;
-
-  for (i = 0; i < NUM_HUFF_TBLS; i++) {
-    cinfo->dc_huff_tbl_ptrs[i] = NULL;
-    cinfo->ac_huff_tbl_ptrs[i] = NULL;
-  }
-
-  /* Initialize marker processor so application can override methods
-   * for COM, APPn markers before calling jpeg_read_header.
-   */
-  cinfo->marker_list = NULL;
-  jinit_marker_reader(cinfo);
-
-  /* And initialize the overall input controller. */
-  jinit_input_controller(cinfo);
-
-  /* OK, I'm ready */
-  cinfo->global_state = DSTATE_START;
-}
-
-
-/*
- * Destruction of a JPEG decompression object
- */
-
-GLOBAL(void)
-jpeg_destroy_decompress (j_decompress_ptr cinfo)
-{
-  jpeg_destroy((j_common_ptr) cinfo); /* use common routine */
-}
-
-
-/*
- * Abort processing of a JPEG decompression operation,
- * but don't destroy the object itself.
- */
-
-GLOBAL(void)
-jpeg_abort_decompress (j_decompress_ptr cinfo)
-{
-  jpeg_abort((j_common_ptr) cinfo); /* use common routine */
-}
-
-
-/*
- * Set default decompression parameters.
- */
-
-LOCAL(void)
-default_decompress_parms (j_decompress_ptr cinfo)
-{
-  /* Guess the input colorspace, and set output colorspace accordingly. */
-  /* (Wish JPEG committee had provided a real way to specify this...) */
-  /* Note application may override our guesses. */
-  switch (cinfo->num_components) {
-  case 1:
-    cinfo->jpeg_color_space = JCS_GRAYSCALE;
-    cinfo->out_color_space = JCS_GRAYSCALE;
-    break;
-    
-  case 3:
-    if (cinfo->saw_JFIF_marker) {
-      cinfo->jpeg_color_space = JCS_YCbCr; /* JFIF implies YCbCr */
-    } else if (cinfo->saw_Adobe_marker) {
-      switch (cinfo->Adobe_transform) {
-      case 0:
-	cinfo->jpeg_color_space = JCS_RGB;
-	break;
-      case 1:
-	cinfo->jpeg_color_space = JCS_YCbCr;
-	break;
-      default:
-	WARNMS1(cinfo, JWRN_ADOBE_XFORM, cinfo->Adobe_transform);
-	cinfo->jpeg_color_space = JCS_YCbCr; /* assume it's YCbCr */
-	break;
-      }
-    } else {
-      /* Saw no special markers, try to guess from the component IDs */
-      int cid0 = cinfo->comp_info[0].component_id;
-      int cid1 = cinfo->comp_info[1].component_id;
-      int cid2 = cinfo->comp_info[2].component_id;
-
-      if (cid0 == 1 && cid1 == 2 && cid2 == 3)
-	cinfo->jpeg_color_space = JCS_YCbCr; /* assume JFIF w/out marker */
-      else if (cid0 == 82 && cid1 == 71 && cid2 == 66)
-	cinfo->jpeg_color_space = JCS_RGB; /* ASCII 'R', 'G', 'B' */
-      else {
-	TRACEMS3(cinfo, 1, JTRC_UNKNOWN_IDS, cid0, cid1, cid2);
-	cinfo->jpeg_color_space = JCS_YCbCr; /* assume it's YCbCr */
-      }
-    }
-    /* Always guess RGB is proper output colorspace. */
-    cinfo->out_color_space = JCS_RGB;
-    break;
-    
-  case 4:
-    if (cinfo->saw_Adobe_marker) {
-      switch (cinfo->Adobe_transform) {
-      case 0:
-	cinfo->jpeg_color_space = JCS_CMYK;
-	break;
-      case 2:
-	cinfo->jpeg_color_space = JCS_YCCK;
-	break;
-      default:
-	WARNMS1(cinfo, JWRN_ADOBE_XFORM, cinfo->Adobe_transform);
-	cinfo->jpeg_color_space = JCS_YCCK; /* assume it's YCCK */
-	break;
-      }
-    } else {
-      /* No special markers, assume straight CMYK. */
-      cinfo->jpeg_color_space = JCS_CMYK;
-    }
-    cinfo->out_color_space = JCS_CMYK;
-    break;
-    
-  default:
-    cinfo->jpeg_color_space = JCS_UNKNOWN;
-    cinfo->out_color_space = JCS_UNKNOWN;
-    break;
-  }
-
-  /* Set defaults for other decompression parameters. */
-  cinfo->scale_num = cinfo->block_size;		/* 1:1 scaling */
-  cinfo->scale_denom = cinfo->block_size;
-  cinfo->output_gamma = 1.0;
-  cinfo->buffered_image = FALSE;
-  cinfo->raw_data_out = FALSE;
-  cinfo->dct_method = JDCT_DEFAULT;
-  cinfo->do_fancy_upsampling = TRUE;
-  cinfo->do_block_smoothing = TRUE;
-  cinfo->quantize_colors = FALSE;
-  /* We set these in case application only sets quantize_colors. */
-  cinfo->dither_mode = JDITHER_FS;
-#ifdef QUANT_2PASS_SUPPORTED
-  cinfo->two_pass_quantize = TRUE;
-#else
-  cinfo->two_pass_quantize = FALSE;
-#endif
-  cinfo->desired_number_of_colors = 256;
-  cinfo->colormap = NULL;
-  /* Initialize for no mode change in buffered-image mode. */
-  cinfo->enable_1pass_quant = FALSE;
-  cinfo->enable_external_quant = FALSE;
-  cinfo->enable_2pass_quant = FALSE;
-}
-
-
-/*
- * Decompression startup: read start of JPEG datastream to see what's there.
- * Need only initialize JPEG object and supply a data source before calling.
- *
- * This routine will read as far as the first SOS marker (ie, actual start of
- * compressed data), and will save all tables and parameters in the JPEG
- * object.  It will also initialize the decompression parameters to default
- * values, and finally return JPEG_HEADER_OK.  On return, the application may
- * adjust the decompression parameters and then call jpeg_start_decompress.
- * (Or, if the application only wanted to determine the image parameters,
- * the data need not be decompressed.  In that case, call jpeg_abort or
- * jpeg_destroy to release any temporary space.)
- * If an abbreviated (tables only) datastream is presented, the routine will
- * return JPEG_HEADER_TABLES_ONLY upon reaching EOI.  The application may then
- * re-use the JPEG object to read the abbreviated image datastream(s).
- * It is unnecessary (but OK) to call jpeg_abort in this case.
- * The JPEG_SUSPENDED return code only occurs if the data source module
- * requests suspension of the decompressor.  In this case the application
- * should load more source data and then re-call jpeg_read_header to resume
- * processing.
- * If a non-suspending data source is used and require_image is TRUE, then the
- * return code need not be inspected since only JPEG_HEADER_OK is possible.
- *
- * This routine is now just a front end to jpeg_consume_input, with some
- * extra error checking.
- */
-
-GLOBAL(int)
-jpeg_read_header (j_decompress_ptr cinfo, boolean require_image)
-{
-  int retcode;
-
-  if (cinfo->global_state != DSTATE_START &&
-      cinfo->global_state != DSTATE_INHEADER)
-    ERREXIT1(cinfo, JERR_BAD_STATE, cinfo->global_state);
-
-  retcode = jpeg_consume_input(cinfo);
-
-  switch (retcode) {
-  case JPEG_REACHED_SOS:
-    retcode = JPEG_HEADER_OK;
-    break;
-  case JPEG_REACHED_EOI:
-    if (require_image)		/* Complain if application wanted an image */
-      ERREXIT(cinfo, JERR_NO_IMAGE);
-    /* Reset to start state; it would be safer to require the application to
-     * call jpeg_abort, but we can't change it now for compatibility reasons.
-     * A side effect is to free any temporary memory (there shouldn't be any).
-     */
-    jpeg_abort((j_common_ptr) cinfo); /* sets state = DSTATE_START */
-    retcode = JPEG_HEADER_TABLES_ONLY;
-    break;
-  case JPEG_SUSPENDED:
-    /* no work */
-    break;
-  }
-
-  return retcode;
-}
-
-
-/*
- * Consume data in advance of what the decompressor requires.
- * This can be called at any time once the decompressor object has
- * been created and a data source has been set up.
- *
- * This routine is essentially a state machine that handles a couple
- * of critical state-transition actions, namely initial setup and
- * transition from header scanning to ready-for-start_decompress.
- * All the actual input is done via the input controller's consume_input
- * method.
- */
-
-GLOBAL(int)
-jpeg_consume_input (j_decompress_ptr cinfo)
-{
-  int retcode = JPEG_SUSPENDED;
-
-  /* NB: every possible DSTATE value should be listed in this switch */
-  switch (cinfo->global_state) {
-  case DSTATE_START:
-    /* Start-of-datastream actions: reset appropriate modules */
-    (*cinfo->inputctl->reset_input_controller) (cinfo);
-    /* Initialize application's data source module */
-    (*cinfo->src->init_source) (cinfo);
-    cinfo->global_state = DSTATE_INHEADER;
-    /*FALLTHROUGH*/
-  case DSTATE_INHEADER:
-    retcode = (*cinfo->inputctl->consume_input) (cinfo);
-    if (retcode == JPEG_REACHED_SOS) { /* Found SOS, prepare to decompress */
-      /* Set up default parameters based on header data */
-      default_decompress_parms(cinfo);
-      /* Set global state: ready for start_decompress */
-      cinfo->global_state = DSTATE_READY;
-    }
-    break;
-  case DSTATE_READY:
-    /* Can't advance past first SOS until start_decompress is called */
-    retcode = JPEG_REACHED_SOS;
-    break;
-  case DSTATE_PRELOAD:
-  case DSTATE_PRESCAN:
-  case DSTATE_SCANNING:
-  case DSTATE_RAW_OK:
-  case DSTATE_BUFIMAGE:
-  case DSTATE_BUFPOST:
-  case DSTATE_STOPPING:
-    retcode = (*cinfo->inputctl->consume_input) (cinfo);
-    break;
-  default:
-    ERREXIT1(cinfo, JERR_BAD_STATE, cinfo->global_state);
-  }
-  return retcode;
-}
-
-
-/*
- * Have we finished reading the input file?
- */
-
-GLOBAL(boolean)
-jpeg_input_complete (j_decompress_ptr cinfo)
-{
-  /* Check for valid jpeg object */
-  if (cinfo->global_state < DSTATE_START ||
-      cinfo->global_state > DSTATE_STOPPING)
-    ERREXIT1(cinfo, JERR_BAD_STATE, cinfo->global_state);
-  return cinfo->inputctl->eoi_reached;
-}
-
-
-/*
- * Is there more than one scan?
- */
-
-GLOBAL(boolean)
-jpeg_has_multiple_scans (j_decompress_ptr cinfo)
-{
-  /* Only valid after jpeg_read_header completes */
-  if (cinfo->global_state < DSTATE_READY ||
-      cinfo->global_state > DSTATE_STOPPING)
-    ERREXIT1(cinfo, JERR_BAD_STATE, cinfo->global_state);
-  return cinfo->inputctl->has_multiple_scans;
-}
-
-
-/*
- * Finish JPEG decompression.
- *
- * This will normally just verify the file trailer and release temp storage.
- *
- * Returns FALSE if suspended.  The return value need be inspected only if
- * a suspending data source is used.
- */
-
-GLOBAL(boolean)
-jpeg_finish_decompress (j_decompress_ptr cinfo)
-{
-  if ((cinfo->global_state == DSTATE_SCANNING ||
-       cinfo->global_state == DSTATE_RAW_OK) && ! cinfo->buffered_image) {
-    /* Terminate final pass of non-buffered mode */
-    if (cinfo->output_scanline < cinfo->output_height)
-      ERREXIT(cinfo, JERR_TOO_LITTLE_DATA);
-    (*cinfo->master->finish_output_pass) (cinfo);
-    cinfo->global_state = DSTATE_STOPPING;
-  } else if (cinfo->global_state == DSTATE_BUFIMAGE) {
-    /* Finishing after a buffered-image operation */
-    cinfo->global_state = DSTATE_STOPPING;
-  } else if (cinfo->global_state != DSTATE_STOPPING) {
-    /* STOPPING = repeat call after a suspension, anything else is error */
-    ERREXIT1(cinfo, JERR_BAD_STATE, cinfo->global_state);
-  }
-  /* Read until EOI */
-  while (! cinfo->inputctl->eoi_reached) {
-    if ((*cinfo->inputctl->consume_input) (cinfo) == JPEG_SUSPENDED)
-      return FALSE;		/* Suspend, come back later */
-  }
-  /* Do final cleanup */
-  (*cinfo->src->term_source) (cinfo);
-  /* We can use jpeg_abort to release memory and reset global_state */
-  jpeg_abort((j_common_ptr) cinfo);
-  return TRUE;
-}
+/*

+ * jdapimin.c

+ *

+ * Copyright (C) 1994-1998, Thomas G. Lane.

+ * Modified 2009 by Guido Vollbeding.

+ * This file is part of the Independent JPEG Group's software.

+ * For conditions of distribution and use, see the accompanying README file.

+ *

+ * This file contains application interface code for the decompression half

+ * of the JPEG library.  These are the "minimum" API routines that may be

+ * needed in either the normal full-decompression case or the

+ * transcoding-only case.

+ *

+ * Most of the routines intended to be called directly by an application

+ * are in this file or in jdapistd.c.  But also see jcomapi.c for routines

+ * shared by compression and decompression, and jdtrans.c for the transcoding

+ * case.

+ */

+

+#define JPEG_INTERNALS

+#include "jinclude.h"

+#include "jpeglib.h"

+

+

+/*

+ * Initialization of a JPEG decompression object.

+ * The error manager must already be set up (in case memory manager fails).

+ */

+

+GLOBAL(void)

+jpeg_CreateDecompress (j_decompress_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_decompress_struct))

+    ERREXIT2(cinfo, JERR_BAD_STRUCT_SIZE, 

+	     (int) SIZEOF(struct jpeg_decompress_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_decompress_struct));

+    cinfo->err = err;

+    cinfo->client_data = client_data;

+  }

+  cinfo->is_decompressor = TRUE;

+

+  /* 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->src = NULL;

+

+  for (i = 0; i < NUM_QUANT_TBLS; i++)

+    cinfo->quant_tbl_ptrs[i] = NULL;

+

+  for (i = 0; i < NUM_HUFF_TBLS; i++) {

+    cinfo->dc_huff_tbl_ptrs[i] = NULL;

+    cinfo->ac_huff_tbl_ptrs[i] = NULL;

+  }

+

+  /* Initialize marker processor so application can override methods

+   * for COM, APPn markers before calling jpeg_read_header.

+   */

+  cinfo->marker_list = NULL;

+  jinit_marker_reader(cinfo);

+

+  /* And initialize the overall input controller. */

+  jinit_input_controller(cinfo);

+

+  /* OK, I'm ready */

+  cinfo->global_state = DSTATE_START;

+}

+

+

+/*

+ * Destruction of a JPEG decompression object

+ */

+

+GLOBAL(void)

+jpeg_destroy_decompress (j_decompress_ptr cinfo)

+{

+  jpeg_destroy((j_common_ptr) cinfo); /* use common routine */

+}

+

+

+/*

+ * Abort processing of a JPEG decompression operation,

+ * but don't destroy the object itself.

+ */

+

+GLOBAL(void)

+jpeg_abort_decompress (j_decompress_ptr cinfo)

+{

+  jpeg_abort((j_common_ptr) cinfo); /* use common routine */

+}

+

+

+/*

+ * Set default decompression parameters.

+ */

+

+LOCAL(void)

+default_decompress_parms (j_decompress_ptr cinfo)

+{

+  /* Guess the input colorspace, and set output colorspace accordingly. */

+  /* (Wish JPEG committee had provided a real way to specify this...) */

+  /* Note application may override our guesses. */

+  switch (cinfo->num_components) {

+  case 1:

+    cinfo->jpeg_color_space = JCS_GRAYSCALE;

+    cinfo->out_color_space = JCS_GRAYSCALE;

+    break;

+    

+  case 3:

+    if (cinfo->saw_JFIF_marker) {

+      cinfo->jpeg_color_space = JCS_YCbCr; /* JFIF implies YCbCr */

+    } else if (cinfo->saw_Adobe_marker) {

+      switch (cinfo->Adobe_transform) {

+      case 0:

+	cinfo->jpeg_color_space = JCS_RGB;

+	break;

+      case 1:

+	cinfo->jpeg_color_space = JCS_YCbCr;

+	break;

+      default:

+	WARNMS1(cinfo, JWRN_ADOBE_XFORM, cinfo->Adobe_transform);

+	cinfo->jpeg_color_space = JCS_YCbCr; /* assume it's YCbCr */

+	break;

+      }

+    } else {

+      /* Saw no special markers, try to guess from the component IDs */

+      int cid0 = cinfo->comp_info[0].component_id;

+      int cid1 = cinfo->comp_info[1].component_id;

+      int cid2 = cinfo->comp_info[2].component_id;

+

+      if (cid0 == 1 && cid1 == 2 && cid2 == 3)

+	cinfo->jpeg_color_space = JCS_YCbCr; /* assume JFIF w/out marker */

+      else if (cid0 == 82 && cid1 == 71 && cid2 == 66)

+	cinfo->jpeg_color_space = JCS_RGB; /* ASCII 'R', 'G', 'B' */

+      else {

+	TRACEMS3(cinfo, 1, JTRC_UNKNOWN_IDS, cid0, cid1, cid2);

+	cinfo->jpeg_color_space = JCS_YCbCr; /* assume it's YCbCr */

+      }

+    }

+    /* Always guess RGB is proper output colorspace. */

+    cinfo->out_color_space = JCS_RGB;

+    break;

+    

+  case 4:

+    if (cinfo->saw_Adobe_marker) {

+      switch (cinfo->Adobe_transform) {

+      case 0:

+	cinfo->jpeg_color_space = JCS_CMYK;

+	break;

+      case 2:

+	cinfo->jpeg_color_space = JCS_YCCK;

+	break;

+      default:

+	WARNMS1(cinfo, JWRN_ADOBE_XFORM, cinfo->Adobe_transform);

+	cinfo->jpeg_color_space = JCS_YCCK; /* assume it's YCCK */

+	break;

+      }

+    } else {

+      /* No special markers, assume straight CMYK. */

+      cinfo->jpeg_color_space = JCS_CMYK;

+    }

+    cinfo->out_color_space = JCS_CMYK;

+    break;

+    

+  default:

+    cinfo->jpeg_color_space = JCS_UNKNOWN;

+    cinfo->out_color_space = JCS_UNKNOWN;

+    break;

+  }

+

+  /* Set defaults for other decompression parameters. */

+  cinfo->scale_num = cinfo->block_size;		/* 1:1 scaling */

+  cinfo->scale_denom = cinfo->block_size;

+  cinfo->output_gamma = 1.0;

+  cinfo->buffered_image = FALSE;

+  cinfo->raw_data_out = FALSE;

+  cinfo->dct_method = JDCT_DEFAULT;

+  cinfo->do_fancy_upsampling = TRUE;

+  cinfo->do_block_smoothing = TRUE;

+  cinfo->quantize_colors = FALSE;

+  /* We set these in case application only sets quantize_colors. */

+  cinfo->dither_mode = JDITHER_FS;

+#ifdef QUANT_2PASS_SUPPORTED

+  cinfo->two_pass_quantize = TRUE;

+#else

+  cinfo->two_pass_quantize = FALSE;

+#endif

+  cinfo->desired_number_of_colors = 256;

+  cinfo->colormap = NULL;

+  /* Initialize for no mode change in buffered-image mode. */

+  cinfo->enable_1pass_quant = FALSE;

+  cinfo->enable_external_quant = FALSE;

+  cinfo->enable_2pass_quant = FALSE;

+}

+

+

+/*

+ * Decompression startup: read start of JPEG datastream to see what's there.

+ * Need only initialize JPEG object and supply a data source before calling.

+ *

+ * This routine will read as far as the first SOS marker (ie, actual start of

+ * compressed data), and will save all tables and parameters in the JPEG

+ * object.  It will also initialize the decompression parameters to default

+ * values, and finally return JPEG_HEADER_OK.  On return, the application may

+ * adjust the decompression parameters and then call jpeg_start_decompress.

+ * (Or, if the application only wanted to determine the image parameters,

+ * the data need not be decompressed.  In that case, call jpeg_abort or

+ * jpeg_destroy to release any temporary space.)

+ * If an abbreviated (tables only) datastream is presented, the routine will

+ * return JPEG_HEADER_TABLES_ONLY upon reaching EOI.  The application may then

+ * re-use the JPEG object to read the abbreviated image datastream(s).

+ * It is unnecessary (but OK) to call jpeg_abort in this case.

+ * The JPEG_SUSPENDED return code only occurs if the data source module

+ * requests suspension of the decompressor.  In this case the application

+ * should load more source data and then re-call jpeg_read_header to resume

+ * processing.

+ * If a non-suspending data source is used and require_image is TRUE, then the

+ * return code need not be inspected since only JPEG_HEADER_OK is possible.

+ *

+ * This routine is now just a front end to jpeg_consume_input, with some

+ * extra error checking.

+ */

+

+GLOBAL(int)

+jpeg_read_header (j_decompress_ptr cinfo, boolean require_image)

+{

+  int retcode;

+

+  if (cinfo->global_state != DSTATE_START &&

+      cinfo->global_state != DSTATE_INHEADER)

+    ERREXIT1(cinfo, JERR_BAD_STATE, cinfo->global_state);

+

+  retcode = jpeg_consume_input(cinfo);

+

+  switch (retcode) {

+  case JPEG_REACHED_SOS:

+    retcode = JPEG_HEADER_OK;

+    break;

+  case JPEG_REACHED_EOI:

+    if (require_image)		/* Complain if application wanted an image */

+      ERREXIT(cinfo, JERR_NO_IMAGE);

+    /* Reset to start state; it would be safer to require the application to

+     * call jpeg_abort, but we can't change it now for compatibility reasons.

+     * A side effect is to free any temporary memory (there shouldn't be any).

+     */

+    jpeg_abort((j_common_ptr) cinfo); /* sets state = DSTATE_START */

+    retcode = JPEG_HEADER_TABLES_ONLY;

+    break;

+  case JPEG_SUSPENDED:

+    /* no work */

+    break;

+  }

+

+  return retcode;

+}

+

+

+/*

+ * Consume data in advance of what the decompressor requires.

+ * This can be called at any time once the decompressor object has

+ * been created and a data source has been set up.

+ *

+ * This routine is essentially a state machine that handles a couple

+ * of critical state-transition actions, namely initial setup and

+ * transition from header scanning to ready-for-start_decompress.

+ * All the actual input is done via the input controller's consume_input

+ * method.

+ */

+

+GLOBAL(int)

+jpeg_consume_input (j_decompress_ptr cinfo)

+{

+  int retcode = JPEG_SUSPENDED;

+

+  /* NB: every possible DSTATE value should be listed in this switch */

+  switch (cinfo->global_state) {

+  case DSTATE_START:

+    /* Start-of-datastream actions: reset appropriate modules */

+    (*cinfo->inputctl->reset_input_controller) (cinfo);

+    /* Initialize application's data source module */

+    (*cinfo->src->init_source) (cinfo);

+    cinfo->global_state = DSTATE_INHEADER;

+    /*FALLTHROUGH*/

+  case DSTATE_INHEADER:

+    retcode = (*cinfo->inputctl->consume_input) (cinfo);

+    if (retcode == JPEG_REACHED_SOS) { /* Found SOS, prepare to decompress */

+      /* Set up default parameters based on header data */

+      default_decompress_parms(cinfo);

+      /* Set global state: ready for start_decompress */

+      cinfo->global_state = DSTATE_READY;

+    }

+    break;

+  case DSTATE_READY:

+    /* Can't advance past first SOS until start_decompress is called */

+    retcode = JPEG_REACHED_SOS;

+    break;

+  case DSTATE_PRELOAD:

+  case DSTATE_PRESCAN:

+  case DSTATE_SCANNING:

+  case DSTATE_RAW_OK:

+  case DSTATE_BUFIMAGE:

+  case DSTATE_BUFPOST:

+  case DSTATE_STOPPING:

+    retcode = (*cinfo->inputctl->consume_input) (cinfo);

+    break;

+  default:

+    ERREXIT1(cinfo, JERR_BAD_STATE, cinfo->global_state);

+  }

+  return retcode;

+}

+

+

+/*

+ * Have we finished reading the input file?

+ */

+

+GLOBAL(boolean)

+jpeg_input_complete (j_decompress_ptr cinfo)

+{

+  /* Check for valid jpeg object */

+  if (cinfo->global_state < DSTATE_START ||

+      cinfo->global_state > DSTATE_STOPPING)

+    ERREXIT1(cinfo, JERR_BAD_STATE, cinfo->global_state);

+  return cinfo->inputctl->eoi_reached;

+}

+

+

+/*

+ * Is there more than one scan?

+ */

+

+GLOBAL(boolean)

+jpeg_has_multiple_scans (j_decompress_ptr cinfo)

+{

+  /* Only valid after jpeg_read_header completes */

+  if (cinfo->global_state < DSTATE_READY ||

+      cinfo->global_state > DSTATE_STOPPING)

+    ERREXIT1(cinfo, JERR_BAD_STATE, cinfo->global_state);

+  return cinfo->inputctl->has_multiple_scans;

+}

+

+

+/*

+ * Finish JPEG decompression.

+ *

+ * This will normally just verify the file trailer and release temp storage.

+ *

+ * Returns FALSE if suspended.  The return value need be inspected only if

+ * a suspending data source is used.

+ */

+

+GLOBAL(boolean)

+jpeg_finish_decompress (j_decompress_ptr cinfo)

+{

+  if ((cinfo->global_state == DSTATE_SCANNING ||

+       cinfo->global_state == DSTATE_RAW_OK) && ! cinfo->buffered_image) {

+    /* Terminate final pass of non-buffered mode */

+    if (cinfo->output_scanline < cinfo->output_height)

+      ERREXIT(cinfo, JERR_TOO_LITTLE_DATA);

+    (*cinfo->master->finish_output_pass) (cinfo);

+    cinfo->global_state = DSTATE_STOPPING;

+  } else if (cinfo->global_state == DSTATE_BUFIMAGE) {

+    /* Finishing after a buffered-image operation */

+    cinfo->global_state = DSTATE_STOPPING;

+  } else if (cinfo->global_state != DSTATE_STOPPING) {

+    /* STOPPING = repeat call after a suspension, anything else is error */

+    ERREXIT1(cinfo, JERR_BAD_STATE, cinfo->global_state);

+  }

+  /* Read until EOI */

+  while (! cinfo->inputctl->eoi_reached) {

+    if ((*cinfo->inputctl->consume_input) (cinfo) == JPEG_SUSPENDED)

+      return FALSE;		/* Suspend, come back later */

+  }

+  /* Do final cleanup */

+  (*cinfo->src->term_source) (cinfo);

+  /* We can use jpeg_abort to release memory and reset global_state */

+  jpeg_abort((j_common_ptr) cinfo);

+  return TRUE;

+}