com32/elflink/ldlinux/msg.c

   1 #include <com32.h>
   2 #include <stdio.h>
   3 #include <bios.h>
   4 #include <graphics.h>
   5
   6 static uint8_t TextAttribute;   /* Text attribute for message file */
   7 extern uint8_t DisplayMask;     /* Display modes mask */
   8
   9 /* Routine to interpret next print char */
  10 static void (*NextCharJump)(uint8_t);
  11
  12 void msg_initvars(void);
  13 static void msg_setfg(uint8_t data);
  14 static void msg_putchar(uint8_t ch);
  15
  16 /*
  17  *
  18  * get_msg_file: Load a text file and write its contents to the screen,
  19  *               interpreting color codes.
  20  *
  21  * Returns 0 on success, -1 on failure.
  22  */
  23 int get_msg_file(char *filename)
  24 {
  25         FILE *f;
  26         char ch;
  27
  28         f = fopen(filename, "r");
  29         if (!f)
  30                 return -1;
  31
  32         TextAttribute = 0x7;    /* Default grey on white */
  33         DisplayMask = 0x7;      /* Display text in all modes */
  34         msg_initvars();
  35
  36         /*
  37          * Read the text file a byte at a time and interpret that
  38          * byte.
  39          */
  40         while ((ch = getc(f)) != EOF) {
  41                 /* DOS EOF? */
  42                 if (ch == 0x1A)
  43                         break;
  44
  45                 NextCharJump(ch);       /* Do what shall be done */
  46         }
  47
  48         DisplayMask = 0x07;
  49
  50         fclose(f);
  51         return 0;
  52 }
  53
  54 static inline int display_mask_vga(void)
  55 {
  56         uint8_t mask = UsingVGA & 0x1;
  57         return (DisplayMask & ++mask);
  58 }
  59
  60 static void msg_setbg(uint8_t data)
  61 {
  62         if (unhexchar(&data) == 0) {
  63                 data <<= 4;
  64                 if (display_mask_vga())
  65                         TextAttribute = data;
  66
  67                 NextCharJump = msg_setfg;
  68         } else {
  69                 TextAttribute = 0x7;    /* Default attribute */
  70                 NextCharJump = msg_putchar;
  71         }
  72 }
  73
  74 static void msg_setfg(uint8_t data)
  75 {
  76         if (unhexchar(&data) == 0) {
  77                 if (display_mask_vga()) {
  78                         /* setbg set foreground to 0 */
  79                         TextAttribute |= data;
  80                 }
  81         } else
  82                 TextAttribute = 0x7;    /* Default attribute */
  83
  84         NextCharJump = msg_putchar;
  85 }
  86
  87 static inline void msg_ctrl_o(void)
  88 {
  89         NextCharJump = msg_setbg;
  90 }
  91
  92 /* Convert ANSI colors to PC display attributes */
  93 static int convert_to_pcdisplay[] = { 0, 4, 2, 6, 1, 5, 3, 7 };
  94
  95 static void set_fgbg(void)
  96 {
  97         uint8_t bg, fg;
  98
  99         fg = convert_to_pcdisplay[(TextAttribute & 0x7)];
 100         bg = convert_to_pcdisplay[((TextAttribute >> 4) & 0x7)];
 101
 102         printf("\033[");
 103         if (TextAttribute & 0x8)
 104                 printf("1;"); /* Foreground bright */
 105
 106         printf("3%dm\033[", fg);
 107
 108         if (TextAttribute & 0x80)
 109                 printf("5;"); /* Foreground blink */
 110
 111         printf("4%dm", bg);
 112 }
 113
 114 static void msg_formfeed(void)
 115 {
 116         set_fgbg();
 117         printf("\033[2J\033[H\033[0m");
 118 }
 119
 120 static void msg_novga(void)
 121 {
 122         syslinux_force_text_mode();
 123         msg_initvars();
 124 }
 125
 126 static void msg_viewimage(void)
 127 {
 128         FILE *f;
 129
 130         *VGAFilePtr = '\0';     /* Zero-terminate filename */
 131
 132         mangle_name(VGAFileMBuf, VGAFileBuf);
 133         f = fopen(VGAFileMBuf, "r");
 134         if (!f) {
 135                 /* Not there */
 136                 NextCharJump = msg_putchar;
 137                 return;
 138         }
 139
 140         vgadisplayfile(f);
 141         fclose(f);
 142         msg_initvars();
 143 }
 144
 145 /*
 146  * Getting VGA filename
 147  */
 148 static void msg_filename(uint8_t data)
 149 {
 150         /* <LF> = end of filename */
 151         if (data == 0x0A) {
 152                 msg_viewimage();
 153                 return;
 154         }
 155
 156         /* Ignore space/control char */
 157         if (data > ' ') {
 158                 if ((char *)VGAFilePtr < (VGAFileBuf + sizeof(VGAFileBuf)))
 159                         *VGAFilePtr++ = data;
 160         }
 161 }
 162
 163 static void msg_vga(void)
 164 {
 165         NextCharJump = msg_filename;
 166         VGAFilePtr = (uint16_t *)VGAFileBuf;
 167 }
 168
 169 static void msg_normal(uint8_t data)
 170 {
 171         /* 0x1 = text mode, 0x2 = graphics mode */
 172         if (!display_mask_vga() || !(DisplayCon & 0x01)) {
 173                 /* Write to serial port */
 174                 if (DisplayMask & 0x4)
 175                         write_serial(data);
 176
 177                 return;         /* Not screen */
 178         }
 179
 180         set_fgbg();
 181         printf("%c\033[0m", data);
 182 }
 183
 184 static void msg_modectl(uint8_t data)
 185 {
 186         data &= 0x07;
 187         DisplayMask = data;
 188         NextCharJump = msg_putchar;
 189 }
 190
 191 static void msg_putchar(uint8_t ch)
 192 {
 193         /* 10h to 17h are mode controls */
 194         if (ch >= 0x10 && ch < 0x18) {
 195                 msg_modectl(ch);
 196                 return;
 197         }
 198
 199         switch (ch) {
 200         case 0x0F:              /* ^O = color code follows */
 201                 msg_ctrl_o();
 202                 break;
 203         case 0x0D:              /* Ignore <CR> */
 204                 break;
 205         case 0x0C:              /* <FF> = clear screen */
 206                 msg_formfeed();
 207                 break;
 208         case 0x19:              /* <EM> = return to text mode */
 209                 msg_novga();
 210                 break;
 211         case 0x18:              /* <CAN> = VGA filename follows */
 212                 msg_vga();
 213                 break;
 214         default:
 215                 msg_normal(ch);
 216                 break;
 217         }
 218 }
 219
 220 /*
 221  * Subroutine to initialize variables, also needed after loading
 222  * graphics file.
 223  */
 224 void msg_initvars(void)
 225 {
 226         /* Initialize state machine */
 227         NextCharJump = msg_putchar;
 228 }