tools/bmp_logo.c

   1 #include "compiler.h"
   2
   3 enum {
   4         MODE_GEN_INFO,
   5         MODE_GEN_DATA
   6 };
   7
   8 typedef struct bitmap_s {               /* bitmap description */
   9         uint16_t width;
  10         uint16_t height;
  11         uint8_t palette[256*3];
  12         uint8_t *data;
  13 } bitmap_t;
  14
  15 #define DEFAULT_CMAP_SIZE       16      /* size of default color map    */
  16
  17 void usage(const char *prog)
  18 {
  19         fprintf(stderr, "Usage: %s [--gen-info|--gen-data] file\n", prog);
  20 }
  21
  22 /*
  23  * Neutralize little endians.
  24  */
  25 uint16_t le_short(uint16_t x)
  26 {
  27     uint16_t val;
  28     uint8_t *p = (uint8_t *)(&x);
  29
  30     val =  (*p++ & 0xff) << 0;
  31     val |= (*p & 0xff) << 8;
  32
  33     return val;
  34 }
  35
  36 void skip_bytes (FILE *fp, int n)
  37 {
  38         while (n-- > 0)
  39                 fgetc (fp);
  40 }
  41
  42 __attribute__ ((__noreturn__))
  43 int error (char * msg, FILE *fp)
  44 {
  45         fprintf (stderr, "ERROR: %s\n", msg);
  46
  47         fclose (fp);
  48
  49         exit (EXIT_FAILURE);
  50 }
  51
  52 void gen_info(bitmap_t *b, uint16_t n_colors)
  53 {
  54         printf("/*\n"
  55                 " * Automatically generated by \"tools/bmp_logo\"\n"
  56                 " *\n"
  57                 " * DO NOT EDIT\n"
  58                 " *\n"
  59                 " */\n\n\n"
  60                 "#ifndef __BMP_LOGO_H__\n"
  61                 "#define __BMP_LOGO_H__\n\n"
  62                 "#define BMP_LOGO_WIDTH\t\t%d\n"
  63                 "#define BMP_LOGO_HEIGHT\t\t%d\n"
  64                 "#define BMP_LOGO_COLORS\t\t%d\n"
  65                 "#define BMP_LOGO_OFFSET\t\t%d\n\n"
  66                 "extern unsigned short bmp_logo_palette[];\n"
  67                 "extern unsigned char bmp_logo_bitmap[];\n\n"
  68                 "#endif /* __BMP_LOGO_H__ */\n",
  69                 b->width, b->height, n_colors,
  70                 DEFAULT_CMAP_SIZE);
  71 }
  72
  73 int main (int argc, char *argv[])
  74 {
  75         int     mode, i, x;
  76         FILE    *fp;
  77         bitmap_t bmp;
  78         bitmap_t *b = &bmp;
  79         uint16_t data_offset, n_colors;
  80
  81         if (argc < 3) {
  82                 usage(argv[0]);
  83                 exit (EXIT_FAILURE);
  84         }
  85
  86         if (!strcmp(argv[1], "--gen-info"))
  87                 mode = MODE_GEN_INFO;
  88         else if (!strcmp(argv[1], "--gen-data"))
  89                 mode = MODE_GEN_DATA;
  90         else {
  91                 usage(argv[0]);
  92                 exit(EXIT_FAILURE);
  93         }
  94
  95         fp = fopen(argv[2], "rb");
  96         if (!fp) {
  97                 perror(argv[2]);
  98                 exit (EXIT_FAILURE);
  99         }
 100
 101         if (fgetc (fp) != 'B' || fgetc (fp) != 'M')
 102                 error ("Input file is not a bitmap", fp);
 103
 104         /*
 105          * read width and height of the image, and the number of colors used;
 106          * ignore the rest
 107          */
 108         skip_bytes (fp, 8);
 109         if (fread (&data_offset, sizeof (uint16_t), 1, fp) != 1)
 110                 error ("Couldn't read bitmap data offset", fp);
 111         skip_bytes (fp, 6);
 112         if (fread (&b->width,   sizeof (uint16_t), 1, fp) != 1)
 113                 error ("Couldn't read bitmap width", fp);
 114         skip_bytes (fp, 2);
 115         if (fread (&b->height,  sizeof (uint16_t), 1, fp) != 1)
 116                 error ("Couldn't read bitmap height", fp);
 117         skip_bytes (fp, 22);
 118         if (fread (&n_colors, sizeof (uint16_t), 1, fp) != 1)
 119                 error ("Couldn't read bitmap colors", fp);
 120         skip_bytes (fp, 6);
 121
 122         /*
 123          * Repair endianess.
 124          */
 125         data_offset = le_short(data_offset);
 126         b->width = le_short(b->width);
 127         b->height = le_short(b->height);
 128         n_colors = le_short(n_colors);
 129
 130         /* assume we are working with an 8-bit file */
 131         if ((n_colors == 0) || (n_colors > 256 - DEFAULT_CMAP_SIZE)) {
 132                 /* reserve DEFAULT_CMAP_SIZE color map entries for default map */
 133                 n_colors = 256 - DEFAULT_CMAP_SIZE;
 134         }
 135
 136         if (mode == MODE_GEN_INFO) {
 137                 gen_info(b, n_colors);
 138                 goto out;
 139         }
 140
 141         printf("/*\n"
 142                 " * Automatically generated by \"tools/bmp_logo\"\n"
 143                 " *\n"
 144                 " * DO NOT EDIT\n"
 145                 " *\n"
 146                 " */\n\n\n"
 147                 "#ifndef __BMP_LOGO_DATA_H__\n"
 148                 "#define __BMP_LOGO_DATA_H__\n\n");
 149
 150         /* allocate memory */
 151         if ((b->data = (uint8_t *)malloc(b->width * b->height)) == NULL)
 152                 error ("Error allocating memory for file", fp);
 153
 154         /* read and print the palette information */
 155         printf("unsigned short bmp_logo_palette[] = {\n");
 156
 157         for (i=0; i<n_colors; ++i) {
 158                 b->palette[(int)(i*3+2)] = fgetc(fp);
 159                 b->palette[(int)(i*3+1)] = fgetc(fp);
 160                 b->palette[(int)(i*3+0)] = fgetc(fp);
 161                 x=fgetc(fp);
 162
 163                 printf ("%s0x0%X%X%X,%s",
 164                         ((i%8) == 0) ? "\t" : "  ",
 165                         (b->palette[(int)(i*3+0)] >> 4) & 0x0F,
 166                         (b->palette[(int)(i*3+1)] >> 4) & 0x0F,
 167                         (b->palette[(int)(i*3+2)] >> 4) & 0x0F,
 168                         ((i%8) == 7) ? "\n" : ""
 169                 );
 170         }
 171
 172         /* seek to offset indicated by file header */
 173         fseek(fp, (long)data_offset, SEEK_SET);
 174
 175         /* read the bitmap; leave room for default color map */
 176         printf ("\n");
 177         printf ("};\n");
 178         printf ("\n");
 179         printf("unsigned char bmp_logo_bitmap[] = {\n");
 180         for (i=(b->height-1)*b->width; i>=0; i-=b->width) {
 181                 for (x = 0; x < b->width; x++) {
 182                         b->data[i + x] = (uint8_t) fgetc(fp)
 183                                                 + DEFAULT_CMAP_SIZE;
 184                 }
 185         }
 186
 187         for (i=0; i<(b->height*b->width); ++i) {
 188                 if ((i%8) == 0)
 189                         putchar ('\t');
 190                 printf ("0x%02X,%c",
 191                         b->data[i],
 192                         ((i%8) == 7) ? '\n' : ' '
 193                 );
 194         }
 195         printf ("\n"
 196                 "};\n\n"
 197                 "#endif /* __BMP_LOGO_DATA_H__ */\n"
 198         );
 199
 200 out:
 201         fclose(fp);
 202         return 0;
 203 }