Bean wrote:
Hi,
I just fix a small bug that can cause color distortion, here is the new patch.
Nice job for implementing JPEG. This is the major reason I made the
bitmap loader interface, to allow other people to write loaders... now
if we would just have PNG support ;)
I will not comment on the JPEG format or any possible IPR issues as I am
not too clear on that myself, just the patch itself.
I would have hoped a bit more comments. Check your tabs and spaces.
Re-check array handling.
I know lots of JPEG loaders seems to use longjmp for error handling,
personally I don't like it, but I suppose it is ok. In grub2 you could
just check if grub_errno != GRUB_ERR_NONE and then just return and at
that level do the same check. This mechanism works a bit like c++'s
exceptions.
Another thing is that if there is a problem loading JPEG, user gets a
message like "invalid marker: 1234", this doesn't really tell user a
thing. So I would propose to use jpeg prefix like "jpeg: invalid
marker...", or more descriptive from user's perspective.
diff --git a/conf/i386-pc.rmk b/conf/i386-pc.rmk
index a46bc74..4beeeff 100644
--- a/conf/i386-pc.rmk
+++ b/conf/i386-pc.rmk
@@ -136,7 +136,7 @@ pkglib_MODULES = biosdisk.mod _chain.mod
_linux.mod linux.mod normal.mod \
_multiboot.mod chain.mod multiboot.mod reboot.mod halt.mod \
vbe.mod vbetest.mod vbeinfo.mod video.mod gfxterm.mod \
videotest.mod play.mod bitmap.mod tga.mod cpuid.mod serial.mod \
- ata.mod vga.mod
+ ata.mod vga.mod jpeg.mod
# For biosdisk.mod.
biosdisk_mod_SOURCES = disk/i386/pc/biosdisk.c
@@ -249,6 +249,11 @@ tga_mod_SOURCES = video/readers/tga.c
tga_mod_CFLAGS = $(COMMON_CFLAGS)
tga_mod_LDFLAGS = $(COMMON_LDFLAGS)
+# For jpeg.mod
+jpeg_mod_SOURCES = video/readers/jpeg.c
+jpeg_mod_CFLAGS = $(COMMON_CFLAGS)
+jpeg_mod_LDFLAGS = $(COMMON_LDFLAGS)
+
# For cpuid.mod.
cpuid_mod_SOURCES = commands/i386/cpuid.c
cpuid_mod_CFLAGS = $(COMMON_CFLAGS)
diff --git a/video/readers/jpeg.c b/video/readers/jpeg.c
new file mode 100755
index 0000000..bcbf820
--- /dev/null
+++ b/video/readers/jpeg.c
@@ -0,0 +1,734 @@
+/*
+ * GRUB -- GRand Unified Bootloader
+ * Copyright (C) 2008 Free Software Foundation, Inc.
+ *
+ * GRUB 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 3 of the License, or
+ * (at your option) any later version.
+ *
+ * GRUB 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 GRUB. If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include <grub/bitmap.h>
+#include <grub/types.h>
+#include <grub/normal.h>
+#include <grub/dl.h>
+#include <grub/mm.h>
+#include <grub/misc.h>
+#include <grub/arg.h>
+#include <grub/file.h>
+#include <grub/setjmp.h>
+
+/* Uncomment following define to enable JPEG debug. */
+//#define JPEG_DEBUG
+
+struct grub_jpeg_data
+{
+ grub_file_t file;
+ grub_jmp_buf jumper;
+
+ int image_width;
+ int image_height;
+
+ grub_uint8_t *huff_value[4];
+ int huff_offset[4][16];
+ int huff_maxval[4][16];
+
+ grub_uint8_t quan_table[2][64];
+ int comp_index[3][3];
+
+ int ydu[4][64], cbdu[64], crdu[64];
+
+ int Cr_r_tab[256], Cb_b_tab[256], Cr_g_tab[256], Cb_g_tab[256];
+
+ int dc_value[3];
+
+ int bit_mask, bit_save;
+
+ struct grub_video_bitmap **bitmap;
+};
+
+static grub_uint8_t
+get_byte (struct grub_jpeg_data *data)
+{
+ grub_uint8_t r;
+
+ if (grub_file_read (data->file, (char *) &r, 1) != 1)
+ grub_longjmp (data->jumper, 1);
+
+ return r;
+}
+
+static unsigned
unsigned -> grub_uint16_t
+get_word (struct grub_jpeg_data *data)
+{
+ unsigned aa, bb;
+
+ aa = get_byte (data);
+ bb = get_byte (data);
+ return (aa << 8) + bb;
+}
+
+static int
+get_bit (struct grub_jpeg_data *data)
+{
+ int ret;
+
+ if (data->bit_mask == 0)
+ {
+ data->bit_save = get_byte (data);
+ if (data->bit_save == 0xFF)
+ {
+ if (get_byte (data) != 0)
+ {
+ grub_error (GRUB_ERR_BAD_FILE_TYPE,
+ "invalid 0xFF in data stream");
+ grub_longjmp (data->jumper, 1);
+ }
+ }
+ data->bit_mask = 0x80;
+ }
+
+ ret = (data->bit_save & data->bit_mask);
+ data->bit_mask >>= 1;
+ return ret;
+}
+
+static int
+get_huff_leng (struct grub_jpeg_data *data, int num)
_length?
+{
+ int value, i, bit;
+
+ if (num == 0)
+ return 0;
+
+ bit = get_bit (data);
+ value = (bit != 0);
+ for (i = 1; i < num; i++)
+ value = value * 2 + (get_bit (data) != 0);
+ if (!bit)
+ value += 1 - (1 << num);
+
+ return value;
+}
+
+static int
+get_huff_base (struct grub_jpeg_data *data, int id)
+{
+ int code, i;
+
+ code = 0;
+ for (i = 0; i < 16; i++)
+ {
+ code <<= 1;
+ if (get_bit (data))
+ code++;
+ if (code < data->huff_maxval[id][i])
+ return data->huff_value[id][code + data->huff_offset[id][i]];
+ }
+ grub_error (GRUB_ERR_BAD_FILE_TYPE, "huffman decode fails");
+ grub_longjmp (data->jumper, 1);
+ return 0;
+}
+
+static void
+decode_huff_table (struct grub_jpeg_data *data)
+{
+ unsigned id;
unsigned -> grub_uint8_t
+ int ac, i, n, base, ofs;
+ grub_uint8_t count[16];
+
+ get_word (data);
not important word?
+ id = get_byte (data);
+ ac = (id >> 4);
+ id &= 0xF;
+ if (id > 1)
+ {
+ grub_error (GRUB_ERR_BAD_FILE_TYPE, "too many huff table");
+ grub_longjmp (data->jumper, 1);
+ }
+
+ if (grub_file_read (data->file, (char *) &count, sizeof (count)) !=
+ sizeof (count))
+ grub_longjmp (data->jumper, 1);
+
+ n = 0;
+ for (i = 0; i < 16; i++)
+ n += count[i];
+
+ id += ac * 2;
+ if ((data->huff_value[id] = grub_malloc (n)) == NULL)
try to keep malloc on own line and then check for pointer or for
grub_errno (or both).
+ grub_longjmp (data->jumper, 1);
+
+ if (grub_file_read (data->file, (char *) data->huff_value[id], n) != n)
+ grub_longjmp (data->jumper, 1);
+
+ base = 0;
+ ofs = 0;
+ for (i = 0; i < 16; i++)
+ {
+ base += count[i];
+ ofs += count[i];
+
+ data->huff_maxval[id][i] = base;
+ data->huff_offset[id][i] = ofs - base;
+
+ base <<= 1;
+ }
+}
+
+static void
+decode_quan_table (struct grub_jpeg_data *data)
+{
+ unsigned id;
+
+ get_word (data);
+ id = get_byte (data);
+ if (id >= 0x10)
0x10?
+ {
+ grub_error (GRUB_ERR_BAD_FILE_TYPE,
+ "only 8-bit precision is supported");
+ grub_longjmp (data->jumper, 1);
+ }
+
+ if (id > 1)
+ {
+ grub_error (GRUB_ERR_BAD_FILE_TYPE, "too many quantization table");
+ grub_longjmp (data->jumper, 1);
+ }
+
+ if (grub_file_read (data->file, (char *) &data->quan_table[id], 64) != 64)
+ grub_longjmp (data->jumper, 1);
+}
+
+static void
+decode_sof (struct grub_jpeg_data *data)
+{
+ int nc, i;
+
+ get_word (data);
+ if (get_byte (data) != 8)
+ {
+ grub_error (GRUB_ERR_BAD_FILE_TYPE,
+ "only 8-bit precision is supported");
+ grub_longjmp (data->jumper, 1);
+ }
+
+ data->image_height = get_word (data);
+ data->image_width = get_word (data);
+
+ if ((!data->image_height) || (!data->image_width))
+ {
+ grub_error (GRUB_ERR_BAD_FILE_TYPE, "invalid image size");
+ grub_longjmp (data->jumper, 1);
+ }
+
+ nc = get_byte (data);
+ if (nc != 3)
+ {
+ grub_error (GRUB_ERR_BAD_FILE_TYPE, "component count must be 3");
+ grub_longjmp (data->jumper, 1);
+ }
+
+ for (i = 0; i < nc; i++)
+ {
+ int id, ss;
+
+ id = get_byte (data) - 1;
+ ss = get_byte (data);
+ if (((!id) && (ss != 0x22)) || ((id) && (ss != 0x11)))
+ {
+ grub_error (GRUB_ERR_BAD_FILE_TYPE, "only support 2:1:1 sampling");
+ grub_longjmp (data->jumper, 1);
+ }
+ data->comp_index[id][0] = get_byte (data);
Buffer overflow possibility.
+ }
+}
+
+#define DCTSIZE 8
+
+#define CONST_BITS 8
+#define PASS1_BITS 2
+
+#define FIX_1_082392200 ((int) 277) /* FIX(1.082392200) */
+#define FIX_1_414213562 ((int) 362) /* FIX(1.414213562) */
+#define FIX_1_847759065 ((int) 473) /* FIX(1.847759065) */
+#define FIX_2_613125930 ((int) 669) /* FIX(2.613125930) */
+
+#define ONE ((long) 1)
+#define DESCALE(x,n) (((x) + (ONE << ((n)-1))) >> (n))
+
+#define MULTIPLY(var,const) DESCALE((var) * (const), CONST_BITS)
+
+static const unsigned char natural_order[64] = {
grub_uint8_t, or just (unsigned) int
+ 0, 1, 8, 16, 9, 2, 3, 10,
+ 17, 24, 32, 25, 18, 11, 4, 5,
+ 12, 19, 26, 33, 40, 48, 41, 34,
+ 27, 20, 13, 6, 7, 14, 21, 28,
+ 35, 42, 49, 56, 57, 50, 43, 36,
+ 29, 22, 15, 23, 30, 37, 44, 51,
+ 58, 59, 52, 45, 38, 31, 39, 46,
+ 53, 60, 61, 54, 47, 55, 62, 63
+};
+
+static const short aanscales[64] = {
use just int (as it is anyway casted to int, and I don't think it is
necessary to save some bytes on here from module.
+ /* precomputed values scaled up by 14 bits */
+ 16384, 22725, 21407, 19266, 16384, 12873, 8867, 4520,
+ 22725, 31521, 29692, 26722, 22725, 17855, 12299, 6270,
+ 21407, 29692, 27969, 25172, 21407, 16819, 11585, 5906,
+ 19266, 26722, 25172, 22654, 19266, 15137, 10426, 5315,
+ 16384, 22725, 21407, 19266, 16384, 12873, 8867, 4520,
+ 12873, 17855, 16819, 15137, 12873, 10114, 6967, 3552,
+ 8867, 12299, 11585, 10426, 8867, 6967, 4799, 2446,
+ 4520, 6270, 5906, 5315, 4520, 3552, 2446, 1247
+};
+
+static void
+idct_transform (int *du)
+{
+ int *pd;
+ int ctr;
+ int tmp0, tmp1, tmp2, tmp3, tmp4, tmp5, tmp6, tmp7;
+ int tmp10, tmp11, tmp12, tmp13;
+ int z5, z10, z11, z12, z13;
+
+ /* Pass 1: process columns from input, store into work array. */
Extra space after last dot.
+
+ pd = du;
+ for (ctr = DCTSIZE; ctr > 0; ctr--)
+ {
+ if ((pd[DCTSIZE * 1] | pd[DCTSIZE * 2] | pd[DCTSIZE * 3] |
+ pd[DCTSIZE * 4] | pd[DCTSIZE * 5] | pd[DCTSIZE * 6] |
+ pd[DCTSIZE * 7]) == 0)
+ {
+ pd[DCTSIZE * 1] = pd[DCTSIZE * 2]
+ = pd[DCTSIZE * 3] = pd[DCTSIZE * 4]
+ = pd[DCTSIZE * 5] = pd[DCTSIZE * 6]
+ = pd[DCTSIZE * 7] = pd[DCTSIZE * 0];
+
+ pd++; /* advance pointers to next column */
+ continue;
+ }
+
+ /* Even part */
+
+ tmp0 = pd[DCTSIZE * 0];
+ tmp1 = pd[DCTSIZE * 2];
+ tmp2 = pd[DCTSIZE * 4];
+ tmp3 = pd[DCTSIZE * 6];
+
+ tmp10 = tmp0 + tmp2; /* phase 3 */
+ tmp11 = tmp0 - tmp2;
+
+ tmp13 = tmp1 + tmp3; /* phases 5-3 */
+ tmp12 = MULTIPLY (tmp1 - tmp3, FIX_1_414213562) - tmp13; /* 2*c4 */
+
+ tmp0 = tmp10 + tmp13; /* phase 2 */
+ tmp3 = tmp10 - tmp13;
+ tmp1 = tmp11 + tmp12;
+ tmp2 = tmp11 - tmp12;
+
+ /* Odd part */
+
+ tmp4 = pd[DCTSIZE * 1];
+ tmp5 = pd[DCTSIZE * 3];
+ tmp6 = pd[DCTSIZE * 5];
+ tmp7 = pd[DCTSIZE * 7];
+
+ z13 = tmp6 + tmp5; /* phase 6 */
+ z10 = tmp6 - tmp5;
+ z11 = tmp4 + tmp7;
+ z12 = tmp4 - tmp7;
+
+ tmp7 = z11 + z13; /* phase 5 */
+ tmp11 = MULTIPLY (z11 - z13, FIX_1_414213562); /* 2*c4 */
+
+ z5 = MULTIPLY (z10 + z12, FIX_1_847759065); /* 2*c2 */
+ tmp10 = MULTIPLY (z12, FIX_1_082392200) - z5; /* 2*(c2-c6) */
+ tmp12 = MULTIPLY (z10, -FIX_2_613125930) + z5; /* -2*(c2+c6) */
+
+
+ tmp6 = tmp12 - tmp7; /* phase 2 */
+ tmp5 = tmp11 - tmp6;
+ tmp4 = tmp10 + tmp5;
+
+ pd[DCTSIZE * 0] = (int) (tmp0 + tmp7);
+ pd[DCTSIZE * 7] = (int) (tmp0 - tmp7);
+ pd[DCTSIZE * 1] = (int) (tmp1 + tmp6);
+ pd[DCTSIZE * 6] = (int) (tmp1 - tmp6);
+ pd[DCTSIZE * 2] = (int) (tmp2 + tmp5);
+ pd[DCTSIZE * 5] = (int) (tmp2 - tmp5);
+ pd[DCTSIZE * 4] = (int) (tmp3 + tmp4);
+ pd[DCTSIZE * 3] = (int) (tmp3 - tmp4);
+
+ pd++; /* advance pointers to next column */
+ }
+
+ /* Pass 2: process rows from work array, store into output array. */
+ /* Note that we must descale the results by a factor of 8 == 2**3, */
+ /* and also undo the PASS1_BITS scaling. */
+
+ pd = du;
+ for (ctr = 0; ctr < DCTSIZE; ctr++)
+ {
+ /* Even part */
+
+ tmp10 = pd[0] + pd[4];
+ tmp11 = pd[0] - pd[4];
+
+ tmp13 = pd[2] + pd[6];
+ tmp12 = MULTIPLY (pd[2] - pd[6], FIX_1_414213562) - tmp13;
+
+ tmp0 = tmp10 + tmp13;
+ tmp3 = tmp10 - tmp13;
+ tmp1 = tmp11 + tmp12;
+ tmp2 = tmp11 - tmp12;
+
+ /* Odd part */
+
+ z13 = pd[5] + pd[3];
+ z10 = pd[5] - pd[3];
+ z11 = pd[1] + pd[7];
+ z12 = pd[1] - pd[7];
+
+ tmp7 = z11 + z13; /* phase 5 */
+ tmp11 = MULTIPLY (z11 - z13, FIX_1_414213562); /* 2*c4 */
+
+ z5 = MULTIPLY (z10 + z12, FIX_1_847759065); /* 2*c2 */
+ tmp10 = MULTIPLY (z12, FIX_1_082392200) - z5; /* 2*(c2-c6) */
+ tmp12 = MULTIPLY (z10, -FIX_2_613125930) + z5; /* -2*(c2+c6) */
+
+ tmp6 = tmp12 - tmp7; /* phase 2 */
+ tmp5 = tmp11 - tmp6;
+ tmp4 = tmp10 + tmp5;
+
+ /* Final output stage: scale down by a factor of 8 and range-limit */
+
+ pd[0] = DESCALE (tmp0 + tmp7, PASS1_BITS + 3) + 128;
+ pd[7] = DESCALE (tmp0 - tmp7, PASS1_BITS + 3) + 128;
+ pd[1] = DESCALE (tmp1 + tmp6, PASS1_BITS + 3) + 128;
+ pd[6] = DESCALE (tmp1 - tmp6, PASS1_BITS + 3) + 128;
+ pd[2] = DESCALE (tmp2 + tmp5, PASS1_BITS + 3) + 128;
+ pd[5] = DESCALE (tmp2 - tmp5, PASS1_BITS + 3) + 128;
+ pd[4] = DESCALE (tmp3 + tmp4, PASS1_BITS + 3) + 128;
+ pd[3] = DESCALE (tmp3 - tmp4, PASS1_BITS + 3) + 128;
+
+ pd += DCTSIZE; /* advance pointer to next row */
+ }
+
+ for (ctr = 0; ctr < 64; ctr++)
+ {
+ if (du[ctr] < 0)
+ du[ctr] = 0;
+ if (du[ctr] > 255)
+ du[ctr] = 255;
+ }
+}
+
+static void
+decode_du (struct grub_jpeg_data *data, int id, int *du)
+{
+ int pos, h1, h2, qt;
+
+ grub_memset (du, 0, sizeof (int) * 64);
du is always that size ? perhaps add warning about it to prototype, or
provide length?
I didn't check for indexes below, verify them.
+
+ qt = data->comp_index[id][0];
+ h1 = data->comp_index[id][1];
+ h2 = data->comp_index[id][2];
+
+ data->dc_value[id] += get_huff_leng (data, get_huff_base (data, h1));
+
+ du[0] =
+ data->dc_value[id] * DESCALE ((int) data->quan_table[qt][0] *
+ (int) aanscales[0], 14 - 2);
+ pos = 1;
+ while (pos < 64)
+ {
+ int num, val;
+
+ num = get_huff_base (data, h2);
+ if (!num)
+ break;
+ val = get_huff_leng (data, num & 0xF);
+ num >>= 4;
+ pos += num;
+ du[natural_order[pos]] =
+ val * DESCALE ((int) data->quan_table[qt][pos] *
+ (int) aanscales[natural_order[pos]], 14 - 2);
+ pos++;
+ }
+
+ idct_transform (du);
+}
+
+#define SCALEBITS 16 /* speediest right-shift on some machines */
+#define ONE_HALF ((int) 1 << (SCALEBITS-1))
+#define FIX(x) ((int) ((x) * (1L<<SCALEBITS) + 0.5))
+
+static void
+build_color_table (struct grub_jpeg_data *data)
+{
+ int i, x;
+
+ for (i = 0, x = -128; i <= 255; i++, x++)
+ {
+ data->Cr_r_tab[i] = (int) (FIX (1.40200) * x + ONE_HALF) >> SCALEBITS;
+ data->Cb_b_tab[i] = (int) (FIX (1.77200) * x + ONE_HALF) >> SCALEBITS;
+ data->Cr_g_tab[i] = (-FIX (0.71414)) * x;
+ data->Cb_g_tab[i] = (-FIX (0.34414)) * x + ONE_HALF;
+ }
+}
+
+static void
+decode_sos (struct grub_jpeg_data *data)
+{
+ int nc, i, r1, c1;
+ grub_uint8_t *ptr;
+
+ get_word (data);
No use for first word?
+ nc = get_byte (data);
+
+ if (nc != 3)
+ {
+ grub_error (GRUB_ERR_BAD_FILE_TYPE, "component count must be 3");
+ grub_longjmp (data->jumper, 1);
+ }
+
+ for (i = 0; i < nc; i++)
+ {
+ int id, ht;
+
+ id = get_byte (data) - 1;
+ ht = get_byte (data);
+ data->comp_index[id][1] = (ht >> 4);
+ data->comp_index[id][2] = (ht & 0xF) + 2;
Buffer overflows.
+ }
+
+ get_byte (data);
+ get_word (data);
+
+ if (grub_video_bitmap_create (data->bitmap, data->image_width,
+ data->image_height,
+ GRUB_VIDEO_BLIT_FORMAT_R8G8B8))
+ grub_longjmp (data->jumper, 1);
+
+ ptr = (*data->bitmap)->data;
+ data->bit_mask = 0x0;
+
+ for (r1 = 0; r1 < (data->image_height >> 4); r1++)
+ for (c1 = 0; c1 < (data->image_width >> 4); c1++)
+ {
+ int r2, c2, r3, c3;
+
+ decode_du (data, 0, &data->ydu[0][0]);
+ decode_du (data, 0, &data->ydu[1][0]);
+
+ decode_du (data, 0, &data->ydu[2][0]);
+ decode_du (data, 0, &data->ydu[3][0]);
+
+ decode_du (data, 1, &data->cbdu[0]);
+ decode_du (data, 2, &data->crdu[0]);
+
+ for (r2 = 0; r2 < 2; r2++)
+ for (c2 = 0; c2 < 2; c2++)
+ for (r3 = 0; r3 < 8; r3++)
+ for (c3 = 0; c3 < 8; c3++)
+ {
+ int i0, i1, i2, cr, cb, dd;
+
+ i0 =
+ ((r1 * 16 + r2 * 8 + r3) * (data->image_width) + c1 * 16 +
+ c2 * 8 + c3) * 3;
+ i1 = r3 * 8 + c3;
+ i2 = (r2 * 32 + c2 * 4) + (r3 >> 1) * 8 + (c3 >> 1);
I have following indexes are correct.... (didn't check them)
+
+ cr = data->crdu[i2];
+ cb = data->cbdu[i2];
+
+ // Red
Try to use C comments. /* ...
+ dd = data->ydu[r2 * 2 + c2][i1] + data->Cr_r_tab[cr];
+ if (dd < 0)
+ dd = 0;
+ ptr[i0] = dd;
+
+ // Green
+ dd =
+ data->ydu[r2 * 2 + c2][i1] +
+ ((data->Cb_g_tab[cb] + data->Cr_g_tab[cr]) >> SCALEBITS);
+ if (dd < 0)
+ dd = 0;
+ ptr[i0 + 1] = dd;
+
+ // Blue
+ dd = data->ydu[r2 * 2 + c2][i1] + data->Cb_b_tab[cb];
+ if (dd < 0)
+ dd = 0;
+ ptr[i0 + 2] = dd;
+ }
+ }
+}
+
+
+static grub_uint8_t
+get_marker (struct grub_jpeg_data *data)
+{
+ grub_uint8_t r;
+
+ r = get_byte (data);
+
+ if (r != 0xFF)
0xFF?
+ {
+ grub_error (GRUB_ERR_BAD_FILE_TYPE, "invalid maker");
+ grub_longjmp (data->jumper, 1);
+ }
+
+ return get_byte (data);
+}
+
+static void
+decode_jpeg (struct grub_jpeg_data *data)
+{
+ build_color_table (data);
+
+ if (get_marker (data) != 0xD8)
0xD8?
+ {
+ grub_error (GRUB_ERR_BAD_FILE_TYPE, "invalid jpeg file");
+ grub_longjmp (data->jumper, 1);
+ }
+
+ while (1)
+ {
+ grub_uint8_t marker;
+
+ marker = get_marker (data);
+#ifdef JPEG_DEBUG
+ grub_printf ("marker: %x\n", marker);
+#endif
+ switch (marker)
+ {
+ case 0xc4:
0xC4 ?
+ decode_huff_table (data);
+ break;
+ case 0xdb:
Same...
+ decode_quan_table (data);
+ break;
+ case 0xc0:
+ decode_sof (data);
+ break;
+ case 0xda:
+ decode_sos (data);
+ break;
+ case 0xd9:
+ return;
+ case 0xe0:
+ case 0xfe:
+ {
+ unsigned sz;
unsigned -> grub_uint16_t
+
+ sz = get_word (data);
+ grub_file_seek (data->file, data->file->offset + sz - 2);
+ break;
+ }
+ default:
+ grub_error (GRUB_ERR_BAD_FILE_TYPE, "unrecognized marker %x",
+ marker);
+ grub_longjmp (data->jumper, 1);
+ }
+ }
+}
+
+static grub_err_t
+grub_video_reader_jpeg (struct grub_video_bitmap **bitmap,
+ const char *filename)
+{
+ grub_file_t file;
+ struct grub_jpeg_data *data;
+
+ file = grub_file_open (filename);
+ if (!file)
+ return grub_errno;
+
+ if ((data = grub_malloc (sizeof (*data))) != NULL)
Separate as two lines.
+ {
+ int i;
+
+ grub_memset (data, 0, sizeof (*data));
+ data->file = file;
+ data->bitmap = bitmap;
+ if (!grub_setjmp (data->jumper))
+ decode_jpeg (data);
+
+ for (i = 0; i < 4; i++)
+ if (data->huff_value[i])
+ grub_free (data->huff_value[i]);
+ grub_free (data);
+ }
+
+ if ((grub_errno != GRUB_ERR_NONE) && (*bitmap))
No need to check for *bitmap
+ {
+ grub_video_bitmap_destroy (*bitmap);
+ *bitmap = 0;
+ }
+
+ grub_file_close (file);
+ return grub_errno;
+}
+
+#if defined(JPEG_DEBUG)
+static grub_err_t
+grub_cmd_jpegtest (struct grub_arg_list *state __attribute__ ((unused)),
+ int argc, char **args)
+{
+ struct grub_video_bitmap *bitmap = 0;
+
+ if (argc != 1)
+ return grub_error (GRUB_ERR_BAD_ARGUMENT, "file name required");
+
+ grub_video_reader_jpeg (&bitmap, args[0]);
+ if (grub_errno != GRUB_ERR_NONE)
+ return grub_errno;
+
+ grub_video_bitmap_destroy (bitmap);
+
+ return GRUB_ERR_NONE;
+}
+#endif
+
+static struct grub_video_bitmap_reader jpg_reader = {
+ .extension = ".jpg",
+ .reader = grub_video_reader_jpeg,
+ .next = 0
+};
+
+static struct grub_video_bitmap_reader jpeg_reader = {
+ .extension = ".jpeg",
+ .reader = grub_video_reader_jpeg,
+ .next = 0
+};
+
+GRUB_MOD_INIT (video_reader_jpeg)
+{
+ grub_video_bitmap_reader_register (&jpg_reader);
+ grub_video_bitmap_reader_register (&jpeg_reader);
+#if defined(JPEG_DEBUG)
+ grub_register_command ("jpegtest", grub_cmd_jpegtest,
+ GRUB_COMMAND_FLAG_BOTH, "jpegtest FILE",
+ "Tests loading of JPEG bitmap.", 0);
+#endif
+}
+
+GRUB_MOD_FINI (video_reader_jpeg)
+{
+#if defined(JPEG_DEBUG)
+ grub_unregister_command ("jpegtest");
+#endif
+ grub_video_bitmap_reader_unregister (&jpeg_reader);
+ grub_video_bitmap_reader_unregister (&jpg_reader);
+}
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