[pnm] Add support for PNM images

Signed-off-by: Michael Brown <mcb30@ipxe.org>

1 files changed, 415 insertions, 0 deletions

diff --git a/src/image/pnm.c b/src/image/pnm.c
new file mode 100644
index 00000000..af9e571a
--- /dev/null
+++ b/src/image/pnm.c
@@ -0,0 +1,415 @@
+/*
+ * Copyright (C) 2013 Michael Brown <mbrown@fensystems.co.uk>.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License as
+ * published by the Free Software Foundation; either version 2 of the
+ * License, or any later version.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
+ * 02110-1301, USA.
+ */
+
+FILE_LICENCE ( GPL2_OR_LATER );
+
+/** @file
+ *
+ * Portable anymap format (PNM)
+ *
+ */
+
+#include <stdlib.h>
+#include <errno.h>
+#include <ctype.h>
+#include <ipxe/image.h>
+#include <ipxe/pixbuf.h>
+#include <ipxe/pnm.h>
+
+/**
+ * Extract PNM ASCII value
+ *
+ * @v image		PNM image
+ * @v pnm		PNM context
+ * @ret value		Value, or negative error
+ */
+static int pnm_ascii ( struct image *image, struct pnm_context *pnm ) {
+	char buf[ pnm->ascii_len + 1 /* NUL */ ];
+	char *endp;
+	size_t len;
+	int value;
+	int in_comment = 0;
+
+	/* Skip any leading whitespace and comments */
+	for ( ; pnm->offset < image->len ; pnm->offset++ ) {
+		copy_from_user ( &buf[0], image->data, pnm->offset,
+				 sizeof ( buf[0] ) );
+		if ( in_comment ) {
+			if ( buf[0] == '\n' )
+				in_comment = 0;
+		} else {
+			if ( buf[0] == '#' ) {
+				in_comment = 1;
+			} else if ( ! isspace ( buf[0] ) ) {
+				break;
+			}
+		}
+	}
+
+	/* Fail if no value is present */
+	len = ( image->len - pnm->offset );
+	if ( len == 0 ) {
+		DBGC ( image, "PNM %s ran out of ASCII data\n", image->name );
+		return -EINVAL;
+	}
+
+	/* Copy ASCII value to buffer and ensure string is NUL-terminated */
+	if ( len > ( sizeof ( buf ) - 1 /* NUL */ ) )
+		len = ( sizeof ( buf ) - 1 /* NUL */ );
+	copy_from_user ( buf, image->data, pnm->offset, len );
+	buf[len] = '\0';
+
+	/* Parse value and update offset */
+	value = strtoul ( buf, &endp, 0 );
+	pnm->offset += ( endp - buf );
+
+	/* Check and skip terminating whitespace character, if present */
+	if ( ( pnm->offset != image->len ) && ( *endp != '\0' ) ) {
+		if ( ! isspace ( *endp ) ) {
+			DBGC ( image, "PNM %s invalid ASCII integer\n",
+			       image->name );
+			return -EINVAL;
+		}
+		pnm->offset++;
+	}
+
+	return value;
+}
+
+/**
+ * Extract PNM binary value
+ *
+ * @v image		PNM image
+ * @v pnm		PNM context
+ * @ret value		Value, or negative error
+ */
+static int pnm_binary ( struct image *image, struct pnm_context *pnm ) {
+	uint8_t value;
+
+	/* Sanity check */
+	if ( pnm->offset == image->len ) {
+		DBGC ( image, "PNM %s ran out of binary data\n",
+		       image->name );
+		return -EINVAL;
+	}
+
+	/* Extract value */
+	copy_from_user ( &value, image->data, pnm->offset, sizeof ( value ) );
+	pnm->offset++;
+
+	return value;
+}
+
+/**
+ * Scale PNM scalar value
+ *
+ * @v image		PNM image
+ * @v pnm		PNM context
+ * @v value		Raw value
+ * @ret value		Scaled value (in range 0-255)
+ */
+static int pnm_scale ( struct image *image, struct pnm_context *pnm,
+		       unsigned int value ) {
+
+	if ( value > pnm->max ) {
+		DBGC ( image, "PNM %s has out-of-range value %d (max %d)\n",
+		       image->name, value, pnm->max );
+		return -EINVAL;
+	}
+	return ( ( 255 * value ) / pnm->max );
+}
+
+/**
+ * Convert PNM bitmap composite value to RGB
+ *
+ * @v composite		Composite value
+ * @v index		Pixel index within this composite value
+ * @ret rgb		24-bit RGB value
+ */
+static uint32_t pnm_bitmap ( uint32_t composite, unsigned int index ) {
+
+	/* Composite value is an 8-bit bitmask */
+	return ( ( ( composite << index ) & 0x80 ) ? 0x000000 : 0xffffff );
+}
+
+/**
+ * Convert PNM greymap composite value to RGB
+ *
+ * @v composite		Composite value
+ * @v index		Pixel index within this composite value
+ * @ret rgb		24-bit RGB value
+ */
+static uint32_t pnm_greymap ( uint32_t composite, unsigned int index __unused ){
+
+	/* Composite value is an 8-bit greyscale value */
+	return ( ( composite << 16 ) | ( composite << 8 ) | composite );
+}
+
+/**
+ * Convert PNM pixmap composite value to RGB
+ *
+ * @v composite		Composite value
+ * @v index		Pixel index within this composite value
+ * @ret rgb		24-bit RGB value
+ */
+static uint32_t pnm_pixmap ( uint32_t composite, unsigned int index __unused ) {
+
+	/* Composite value is already an RGB value */
+	return composite;
+}
+
+/**
+ * Extract PNM pixel data
+ *
+ * @v image		PNM image
+ * @v pnm		PNM context
+ * @v pixbuf		Pixel buffer
+ * @ret rc		Return status code
+ */
+static int pnm_data ( struct image *image, struct pnm_context *pnm,
+		      struct pixel_buffer *pixbuf ) {
+	struct pnm_type *type = pnm->type;
+	size_t offset = 0;
+	unsigned int xpos = 0;
+	int scalar;
+	uint32_t composite;
+	uint32_t rgb;
+	unsigned int i;
+
+	/* Fill pixel buffer */
+	while ( offset < pixbuf->len ) {
+
+		/* Extract a scaled composite scalar value from the file */
+		composite = 0;
+		for ( i = 0 ; i < type->depth ; i++ ) {
+			scalar = type->scalar ( image, pnm );
+			if ( scalar < 0 )
+				return scalar;
+			scalar = pnm_scale ( image, pnm, scalar );
+			if ( scalar < 0 )
+				return scalar;
+			composite = ( ( composite << 8 ) | scalar );
+		}
+
+		/* Extract 24-bit RGB values from composite value */
+		for ( i = 0 ; i < type->packing ; i++ ) {
+			if ( offset >= pixbuf->len ) {
+				DBGC ( image, "PNM %s has too many pixels\n",
+				       image->name );
+				return -EINVAL;
+			}
+			rgb = type->rgb ( composite, i );
+			copy_to_user ( pixbuf->data, offset, &rgb,
+				       sizeof ( rgb ) );
+			offset += sizeof ( rgb );
+			if ( ++xpos == pixbuf->width ) {
+				xpos = 0;
+				break;
+			}
+		}
+	}
+
+	return 0;
+}
+
+/** PNM image types */
+static struct pnm_type pnm_types[] = {
+	{
+		.type = '1',
+		.depth = 1,
+		.packing = 1,
+		.flags = PNM_BITMAP,
+		.scalar = pnm_ascii,
+		.rgb = pnm_bitmap,
+	},
+	{
+		.type = '2',
+		.depth = 1,
+		.packing = 1,
+		.scalar = pnm_ascii,
+		.rgb = pnm_greymap,
+	},
+	{
+		.type = '3',
+		.depth = 3,
+		.packing = 1,
+		.scalar = pnm_ascii,
+		.rgb = pnm_pixmap,
+	},
+	{
+		.type = '4',
+		.depth = 1,
+		.packing = 8,
+		.flags = PNM_BITMAP,
+		.scalar = pnm_binary,
+		.rgb = pnm_bitmap,
+	},
+	{
+		.type = '5',
+		.depth = 1,
+		.packing = 1,
+		.scalar = pnm_binary,
+		.rgb = pnm_greymap,
+	},
+	{
+		.type = '6',
+		.depth = 3,
+		.packing = 1,
+		.scalar = pnm_binary,
+		.rgb = pnm_pixmap,
+	},
+};
+
+/**
+ * Determine PNM image type
+ *
+ * @v image		PNM image
+ * @ret type		PNM image type, or NULL if not found
+ */
+static struct pnm_type * pnm_type ( struct image *image ) {
+	struct pnm_signature signature;
+	struct pnm_type *type;
+	unsigned int i;
+
+	/* Extract signature */
+	assert ( image->len >= sizeof ( signature ) );
+	copy_from_user ( &signature, image->data, 0, sizeof ( signature ) );
+
+	/* Check for supported types */
+	for ( i = 0 ; i < ( sizeof ( pnm_types ) /
+			    sizeof ( pnm_types[0] ) ) ; i++ ) {
+		type = &pnm_types[i];
+		if ( type->type == signature.type )
+			return type;
+	}
+	return NULL;
+}
+
+/**
+ * Convert PNM image to pixel buffer
+ *
+ * @v image		PNM image
+ * @v pixbuf		Pixel buffer to fill in
+ * @ret rc		Return status code
+ */
+static int pnm_pixbuf ( struct image *image, struct pixel_buffer **pixbuf ) {
+	struct pnm_context pnm;
+	int width;
+	int height;
+	int max;
+	int rc;
+
+	/* Initialise PNM context */
+	pnm.type = pnm_type ( image );
+	if ( ! pnm.type ) {
+		rc = -ENOTSUP;
+		goto err_type;
+	}
+	pnm.offset = sizeof ( struct pnm_signature );
+	pnm.ascii_len = PNM_ASCII_LEN;
+
+	/* Extract width */
+	if ( ( width = pnm_ascii ( image, &pnm ) ) < 0 ) {
+		rc = width;
+		goto err_width;
+	}
+
+	/* Extract height */
+	if ( ( height = pnm_ascii ( image, &pnm ) ) < 0 ) {
+		rc = height;
+		goto err_height;
+	}
+
+	/* Extract maximum scalar value, if not predefined */
+	if ( pnm.type->flags & PNM_BITMAP ) {
+		pnm.max = ( ( 1 << pnm.type->packing ) - 1 );
+		pnm.ascii_len = 1;
+	} else {
+		if ( ( max = pnm_ascii ( image, &pnm ) ) < 0 ) {
+			rc = max;
+			goto err_max;
+		}
+		pnm.max = max;
+	}
+	if ( pnm.max == 0 ) {
+		DBGC ( image, "PNM %s has invalid maximum value 0\n",
+		       image->name );
+		rc = -EINVAL;
+		goto err_max;
+	}
+	DBGC ( image, "PNM %s is type %c width %d height %d max %d\n",
+	       image->name, pnm.type->type, width, height, pnm.max );
+
+	/* Allocate pixel buffer */
+	*pixbuf = alloc_pixbuf ( width, height );
+	if ( ! *pixbuf ) {
+		rc = -ENOMEM;
+		goto err_alloc_pixbuf;
+	}
+
+	/* Extract pixel data */
+	if ( ( rc = pnm_data ( image, &pnm, *pixbuf ) ) != 0 )
+		goto err_data;
+
+	return 0;
+
+ err_data:
+	pixbuf_put ( *pixbuf );
+ err_alloc_pixbuf:
+ err_max:
+ err_height:
+ err_width:
+ err_type:
+	return rc;
+}
+
+/**
+ * Probe PNM image
+ *
+ * @v image		PNM image
+ * @ret rc		Return status code
+ */
+static int pnm_probe ( struct image *image ) {
+	struct pnm_signature signature;
+
+	/* Sanity check */
+	if ( image->len < sizeof ( signature ) ) {
+		DBGC ( image, "PNM %s is too short\n", image->name );
+		return -ENOEXEC;
+	}
+
+	/* Check signature */
+	copy_from_user ( &signature, image->data, 0, sizeof ( signature ) );
+	if ( ! ( ( signature.magic == PNM_MAGIC ) &&
+		 ( isdigit ( signature.type ) ) &&
+		 ( isspace ( signature.space ) ) ) ) {
+		DBGC ( image, "PNM %s has invalid signature\n", image->name );
+		return -ENOEXEC;
+	}
+	DBGC ( image, "PNM %s is type %c\n", image->name, signature.type );
+
+	return 0;
+}
+
+/** PNM image type */
+struct image_type pnm_image_type __image_type ( PROBE_NORMAL ) = {
+	.name = "PNM",
+	.probe = pnm_probe,
+	.pixbuf = pnm_pixbuf,
+};