/* common */
#include "cmdline.h"
#include "print.h"
+#include "strbuf.h"
#include "xmalloc.h"
#include "version.h"
*
* Header portion:
* .byte $54, $43, $48, $00 ; "TCH" version
- * .word <size of following data>
+ * .word <size of char definitions>
* Data portion:
- * .byte <number of chars in font> ; Value from $81
- * .byte <ascii value of first char> ; Value from $84
* .byte <top> ; Value from $88
* .byte <baseline> ; Value from $89
* .byte <bottom> ; Negative value from $8A
- * .word <char definition offsets>, ... ; Relative to data portion
+ * .byte <width>, ... ; $5F width bytes
+ * .word <char definition offset>, ... ; $5F char def offsets
* Character definitions:
- * .byte <width>
- * .word <converted opcode>, ...
+ * .word <converted opcode>, ...
* .byte $80
*
- * The opcodes get converted for easier handling: END is marked by bit 7
+ * The opcodes get converted for easier handling: END is marked by bit 7
* set in the first byte. The second byte of this opcode is not needed.
* Bit 7 of the second byte marks a MOVE (bit 7 = 0) or DRAW (bit 7 = 1).
*
- * The parsing code does not expect the file to contain more than $7D
- * characters (most will contain $5E or similar), therefore the character
- * definition offset will be accessed using the pointer to the data portion
- * plus an offset in an 8 bit index register.
+ * The number of characters is fixed to $20..$7E (space to tilde), so character
+ * widths and offsets can be stored in fixed size preallocated tables. The
+ * space for the character definitions is allocated on the heap, it's size
+ * is stored in the header.
*
* Above structure allows a program to read the header portion of the file,
- * validate it, allocate memory for the data portion and read the data portion
- * in one chunk into memory. The character definition offsets will then be
- * converted into pointers by adding the data portion pointer to each.
+ * validate it, read the width and offset tables into static storage, allocate
+ * memory for the character definitions read them into memory in one chunk.
+ * The character definition offsets will then be converted into pointers by
+ * adding the character definition base pointer to each.
*/
static void OptVersion (const char* Opt attribute ((unused)),
- const char* Arg attribute ((unused)))
+ const char* Arg attribute ((unused)))
/* Print the assembler version */
{
fprintf (stderr,
-static void ConvertFile (const char* Name)
+static void ConvertChar (StrBuf* Data, const unsigned char* Buf)
+/* Convert data for one character. Original data is in Buf, converted data
+ * will be placed in Data.
+ */
+{
+ /* We should check here for reading past the end of the buffer in case the
+ * input data is not sane.
+ */
+ while (1) {
+
+ /* Get the next op word */
+ unsigned Op = (Buf[0] + (Buf[1] << 8)) & 0x8080;
+
+ /* Check the opcode */
+ switch (Op) {
+
+ case 0x0000:
+ /* End */
+ SB_AppendChar (Data, 0x80);
+ return;
+
+ case 0x0080:
+ /* Move */
+ SB_AppendChar (Data, Buf[0] & 0x7F);
+ SB_AppendChar (Data, Buf[1] & 0x7F);
+ break;
+
+ case 0x8000:
+ /* Invalid opcode */
+ Error ("Input file contains invalid opcode 0x8000");
+ break;
+
+ case 0x8080:
+ /* Draw */
+ SB_AppendChar (Data, Buf[0] & 0x7F);
+ SB_AppendChar (Data, Buf[1] | 0x80);
+ break;
+ }
+
+ /* Next Op */
+ Buf += 2;
+ }
+}
+
+
+
+static void ConvertFile (const char* Input, const char* Output)
/* Convert one vector font file */
{
+ /* The header of a BGI vector font file */
static const unsigned char ChrHeader[] = {
0x50, 0x4B, 0x08, 0x08, 0x42, 0x47, 0x49, 0x20
};
+ /* The header of a TGI vector font file */
+ unsigned char TchHeader[] = {
+ 0x54, 0x43, 0x48, 0x00, /* "TCH" version */
+ 0x00, 0x00, /* size of char definitions */
+ 0x00, /* Top */
+ 0x00, /* Baseline */
+ 0x00, /* Bottom */
+ };
+
long Size;
unsigned char* Buf;
unsigned char* MsgEnd;
+ unsigned FirstChar;
+ unsigned CharCount;
+ unsigned LastChar;
+ unsigned Char;
+ unsigned Offs;
+ const unsigned char* OffsetBuf;
+ const unsigned char* WidthBuf;
+ const unsigned char* VectorBuf;
+ StrBuf Offsets = AUTO_STRBUF_INITIALIZER;
+ StrBuf VectorData = AUTO_STRBUF_INITIALIZER;
+
/* Try to open the file for reading */
- FILE* F = fopen (Name, "rb");
+ FILE* F = fopen (Input, "rb");
if (F == 0) {
- Error ("Cannot open `%s': %s", Name, strerror (errno));
+ Error ("Cannot open input file `%s': %s", Input, strerror (errno));
}
/* Seek to the end and determine the size */
/* Check if the size is reasonable */
if (Size > 32*1024) {
- Error ("File `%s' is too large (max = 32k)", Name);
+ Error ("Input file `%s' is too large (max = 32k)", Input);
} else if (Size < 0x100) {
- Error ("File `%s' is too small to be a vector font file", Name);
+ Error ("Input file `%s' is too small to be a vector font file", Input);
}
/* Allocate memory for the file */
/* Read the file contents into the buffer */
if (fread (Buf, 1, (size_t) Size, F) != (size_t) Size) {
- Error ("Error reading from `%s'", Name);
+ Error ("Error reading from input file `%s'", Input);
}
/* Close the file */
- fclose (F);
+ (void) fclose (F);
/* Verify the header */
if (memcmp (Buf, ChrHeader, sizeof (ChrHeader)) != 0) {
- Error ("Invalid format for `%s': invalid header", Name);
+ Error ("Invalid format for `%s': invalid header", Input);
}
MsgEnd = memchr (Buf + sizeof (ChrHeader), 0x1A, 0x80);
if (MsgEnd == 0) {
- Error ("Invalid format for `%s': description not found", Name);
+ Error ("Invalid format for `%s': description not found", Input);
}
if (MsgEnd[1] != 0x80 || MsgEnd[2] != 0x00) {
- Error ("Invalid format for `%s': wrong header size", Name);
+ Error ("Invalid format for `%s': wrong header size", Input);
+ }
+
+ /* We expect the file to hold chars from 0x20 (space) to 0x7E (tilde) */
+ FirstChar = Buf[0x84];
+ CharCount = Buf[0x81] + (Buf[0x82] << 8);
+ LastChar = FirstChar + CharCount - 1;
+ if (FirstChar < 0x20 || LastChar < 0x7E) {
+ Error ("File `%s' doesn't contain the chars we need", Input);
+ } else if (LastChar >= 0x100) {
+ Error ("File `%s' contains too many character definitions", Input);
}
/* Print the copyright from the header */
Print (stderr, 1, "%.*s\n", (int) (MsgEnd - Buf - 4), Buf+4);
- /* Convert the buffer into a strokefont structure */
+ /* Get pointers to the width table, the offset table and the vector data
+ * table. The first two corrected for 0x20 as first entry.
+ */
+ OffsetBuf = Buf + 0x90 + ((0x20 - FirstChar) * 2);
+ WidthBuf = Buf + 0x90 + (CharCount * 2) + (0x20 - FirstChar);
+ VectorBuf = Buf + 0x90 + (CharCount * 3);
+
+ /* Convert the characters */
+ for (Char = 0x20; Char <= 0x7E; ++Char, OffsetBuf += 2) {
+
+ /* Add the offset to the offset table */
+ Offs = SB_GetLen (&VectorData);
+ SB_AppendChar (&Offsets, Offs & 0xFF);
+ SB_AppendChar (&Offsets, (Offs >> 8) & 0xFF);
+
+ /* Get the offset of the vector data in the BGI data buffer */
+ Offs = OffsetBuf[0] + (OffsetBuf[1] << 8);
+
+ /* Check if the offset is valid */
+ if (Offs + (VectorBuf - Buf) > Size) {
+ Error ("Invalid data offset in input file `%s'", Input);
+ }
+ /* Convert the vector data and place it into the buffer */
+ ConvertChar (&VectorData, VectorBuf + Offs);
+ }
+
+ /* Complete the TCH header */
+ Offs = SB_GetLen (&VectorData);
+ TchHeader[4] = Offs & 0xFF;
+ TchHeader[5] = (Offs >> 8) & 0xFF;
+ TchHeader[6] = Buf[0x88];
+ TchHeader[7] = Buf[0x89];
+ TchHeader[8] = (unsigned char) -(signed char)(Buf[0x8A]);
+
+ /* Open the output file */
+ F = fopen (Output, "wb");
+ if (F == 0) {
+ Error ("Cannot open output file `%s': %s", Output, strerror (errno));
+ }
+
+ /* Write the header to the output file */
+ if (fwrite (TchHeader, 1, sizeof (TchHeader), F) != sizeof (TchHeader)) {
+ Error ("Error writing to `%s' (disk full?)", Output);
+ }
+
+ /* Write the width table to the output file */
+ if (fwrite (WidthBuf, 1, 0x5F, F) != 0x5F) {
+ Error ("Error writing to `%s' (disk full?)", Output);
+ }
+
+ /* Write the offsets to the output file */
+ if (fwrite (SB_GetConstBuf (&Offsets), 1, 0x5F * 2, F) != 0x5F * 2) {
+ Error ("Error writing to `%s' (disk full?)", Output);
+ }
+
+ /* Write the data to the output file */
+ if (fwrite (SB_GetConstBuf (&VectorData), 1, Offs, F) != Offs) {
+ Error ("Error writing to `%s' (disk full?)", Output);
+ }
+
+ /* Close the output file */
+ if (fclose (F) != 0) {
+ Error ("Error closing to `%s': %s", Output, strerror (errno));
+ }
+ /* Done */
}
{
/* Program long options */
static const LongOpt OptTab[] = {
- { "--help", 0, OptHelp },
+ { "--help", 0, OptHelp },
{ "--verbose", 0, OptVerbose },
{ "--version", 0, OptVersion },
};
}
} else {
/* Filename. Dump it. */
- ConvertFile (Arg);
+ ConvertFile (Arg, "out.tch");
++FilesProcessed;
}
projects / cc65 / commitdiff