geowrite2rtf.c

// geowrite2rtf by Michael Steil
//
// Based on this documentation:
// http://unusedino.de/ec64/technical/formats/cvt.html
// http://www.zimmers.net/geos/docs/writefile.txt

#include <stdio.h>
#include <stdlib.h>
#include <libgen.h>
#include <string.h>

// Enable this to convert page breaks into line breaks.
// You will want this for assembly source files, for example.
//#define FF_TO_LF

// You probably want to turn this on. GeoWrite files end in a \0 character.
#define SUPPRESS_NUL

// Turn this on to debug this tool... or broken files.
//#define DEBUG

#ifdef DEBUG
#undef SUPPRESS_NUL
#undef FF_TO_LF
#define debug_printf printf
#else
#define debug_printf(...)
#endif

int
main(int argc, char **argv)
{
	if (argc < 3) {
		fprintf(stderr, "Usage: %s <infile> <outfile.rtf|outfile.html|outfile.txt>\n", basename(argv[0]));
		fprintf(stderr, "\nThis tool converts a C64/C128 GEOS GeoWrite .CVT file into an RTF, HTML,\n");
		fprintf(stderr, "or plain-text file, depending on the file extension of <outfile>.\n");
		fprintf(stderr, "All graphics information will be discarded. Choose RTF for best results.\n");
		return 1;
	}

	char *infile = argv[1];
	char *outfile = argv[2];

	// find out whether we're supposed to output HTML
	int print_html = 0;
	int print_rtf = 0;
	size_t outfile_len = strlen(outfile);
	const char *html_suffix = ".html";
	const char *rtf_suffix = ".rtf";
	size_t html_suffix_len = strlen(html_suffix);
	size_t rtf_suffix_len = strlen(rtf_suffix);
	if (outfile_len >= html_suffix_len && !strcmp(outfile + outfile_len - html_suffix_len, html_suffix) ){
		print_html = 1;
	}
	if (outfile_len >= rtf_suffix_len && !strcmp(outfile + outfile_len - rtf_suffix_len, rtf_suffix) ){
		print_rtf = 1;
	}

	// read the whole file into memory
	char data[1024*1024]; // highly unlikely to be bigger than this
	FILE *f = fopen(infile, "r");
	size_t size = fread(data, 1, sizeof(data), f);
	fclose(f);
	f = fopen(outfile, "w");

	char *format = &data[30];
	char broken;
	if (!strcmp(format, "PRG formatted GEOS file")) {
		// broken CVT file created by DirMaster
		broken = 1;
	} else if (!strcmp(format, "PRG formatted GEOS file V1.0")) {
		broken = 0;
	} else {
		fprintf(stderr, "Unknown file format: %s\n", format);
		return 1;
	}
	debug_printf("<<<%s>>>", format);

	// this is where the payload starts in the file
	char *payload = &data[0x2FA];

	if (print_rtf) {
		fprintf(f, "{\\rtf1 ");
	}

	// the record data is 127 two byte records starting here
	unsigned char *record = (unsigned char *)&data[0x1FC];
	for (int i = 0; i < 61; i++) { // max 61 pages
		unsigned char a1 = record[i * 2];
		unsigned char a2 = record[i * 2 + 1];
		debug_printf("<<<chain 0x%02x/0x%02x>>>", a1, a2);
		// end of file
		if (a1 == 0x00 && a2 == 0x00)
			break;
		if (a1 == 0x00 && a2 == 0xFF)
			continue;

		// size = number of blocks plus extra bytes
		size_t chain_size;
		size_t gross_size;
		if (broken) {
			chain_size = a1 * 254 + a2;
			gross_size = chain_size;
		} else {
			chain_size = (a1 - 1) * 254 + a2 - 1;
			gross_size = a1 * 254;
		}

		char style = 0;
		int font_size = 0;
		for (int j = 0; j < chain_size; j++) {
			unsigned char c = payload[j];

			if (j == 0 && c == 0) {
				// Unknown Escape 0x00 (V1.1 only)
				debug_printf("<<<Unknown Escape 0x00>>>");
				j += 19;
				continue;
			}

			switch (c) {
#ifdef SUPPRESS_NUL
				case 0x0:
					continue;
#endif
				case 0x0c:
#ifdef FF_TO_LF
					fprintf(f, "\n");
					continue;
#else
					if (print_html) {
						fprintf(f, "<hr/>");
						continue;
					} else {
						break;
					}
#endif
				case 0x0d:
					if (print_html) {
						fprintf(f, "<br/>");
					} else if (print_rtf) {
						fprintf(f, "\\\n");
					} else {
						fprintf(f, "\n");
					}
					continue;
				case 0x10:
					// Graphics Escape
					// TODO: We should decode it
					debug_printf("<<<Graphics Escape>>>");
					unsigned char *escape = (unsigned char *)&payload[j + 1];
					unsigned short width = escape[0] * 8;
					unsigned short height = escape[1] | (escape[2] << 8);
					unsigned char record_no = escape[3];
#if 0 // we don't create the attachment file yet
					if (print_rtf) {
						fprintf(f, "{{\\NeXTGraphic attachment \\width%d \\height%d} ¬}", width * 20, height * 20);
					}
#endif
					fprintf(stderr, "%s: Warning: Dropping inline image (%d x %d)!\n", infile, width, height);
					j += 4;
					continue;
				case 0x11: {
					// Ruler Escape
					// TODO: We should decode more
					debug_printf("\n<<<Ruler Escape>>>\n");
					unsigned char *escape = (unsigned char *)&payload[j + 1];
					unsigned char alignment = escape[22] & 3;
					unsigned char spacing = (escape[22] >> 2) & 3;
					unsigned short left = escape[0] | (escape[1] << 8);
					unsigned short right = escape[2] | (escape[3] << 8);
					unsigned short tab[8];
					for (int i = 0; i < 8; i++) {
						tab[i] = escape[4 + 2 * i] | (escape[5 + 2 * i] << 8);
					}
					unsigned short paragraph = escape[20] | (escape[21] << 8);
					unsigned char color = escape[23];
					debug_printf("<<<L/P/R Margin %d/%d/%d>>>\n", left, paragraph, right);
					debug_printf("<<<Tabs:");
					for (int i = 0; i < 8; i++) {
						debug_printf(" %d", tab[i]);
					}
					debug_printf(">>>\n");
					debug_printf("<<<Color %d>>>\n", color);
					debug_printf("<<<Spacing %d>>>\n", spacing);
					debug_printf("\n");

					// tab stops
					if (print_rtf) {
						fprintf(f, "\\pard");
						for (int i = 0; i < 8; i++) {
							if (tab[i] & 0x8000) {
								fprintf(f, "\\tqdec"); // next tab stop is decimal
							}
							fprintf(f, "\\tx%d", (tab[i] & 0x7FFF) * 20);
						}
						fprintf(f, " ");
					} else if (print_html) {
						fprintf(stderr, "%s: Warning: Dropping tab stops!\n", infile);
					}

					// indent
					if (print_rtf) {
						fprintf(f, "\\li%d\\fi%d\\ri%d ", left * 20, (paragraph - left) * 20, right * 20);
					} else if (print_html) {
						fprintf(stderr, "%s: Warning: Dropping line indent!\n", infile);
					}

					// spacing
					if (print_rtf) {
						switch (spacing) {
							case 0:
								fprintf(f, "\\sl240 ");
								break;
							case 1:
								fprintf(f, "\\sl360 ");
								break;
							case 2:
								fprintf(f, "\\sl480 ");
								break;
						}
					} else if (print_html) {
						if (spacing) {
							fprintf(stderr, "%s: Warning: Dropping line spacing!\n", infile);
						}
					}

					// alignment
					char *s;
					switch (alignment) {
						case 0:
							s = "left";
							break;
						case 1:
							s = "center";
							break;
						case 2:
							s = "right";
							break;
						case 3:
							s = "justify";
							break;
					}
					if (print_html) {
						fprintf(f, "<span align=\"%s\">", s);
					} else if (print_rtf) {
						fprintf(f, "\\q%c ", s[0]);
					}

					// text color
					if ((print_html || print_rtf) && color) {
						fprintf(stderr, "%s: Warning: Dropping text color %d!\n", infile, color);
					}
					j += 26;
					continue;
				}
				case 0x17: {
					// NewCardSet Escape (i.e. font/style change)
					unsigned char *escape = (unsigned char *)&payload[j + 1];
					debug_printf("<<<NewCardSet Escape %02x/%02x/%02x>>>", escape[0], escape[1], escape[2]);

					if (print_html || print_rtf) {
						int new_font = escape[0] | escape[1] << 8;
						int new_font_id = new_font >> 5;
						int new_font_size = new_font & 0x1F;
						debug_printf("<<<Font Id=%d Size=%d>>>", new_font_id, new_font_size);
						if (new_font_size != font_size) {
							if (print_html) {
								fprintf(f, "<span style=\"font-size: %dpt\">", new_font_size);
							} else {
								fprintf(f, "\\fs%d ", new_font_size * 2);
							}
							font_size = new_font_size;
						}

						char new_style = escape[2];
						for (int on = 0; on <= 1; on++) {
							for (int b = 1; b < 8; b++) {
								char bit = (style >> b) & 1;
								char new_bit = (new_style >> b) & 1;
								if (bit != new_bit && new_bit == on) {
									if (print_html) {
										if (new_bit) {
											fprintf(f, "<");
										} else {
											fprintf(f, "</");
										}
										switch (b) {
											case 7:
												fprintf(f, "u");
												break;
											case 6:
												fprintf(f, "b");
												break;
											case 5:
												fprintf(f, "reverse"); // XXX not an actual HTML tag
												break;
											case 4:
												fprintf(f, "i");
												break;
											case 3:
												fprintf(f, "outline"); // XXX not an actual HTML tag
												break;
											case 2:
												fprintf(f, "sup");
												break;
											case 1:
												fprintf(f, "sub");
												break;
										}
										fprintf(f, ">");
									} else {
										switch (b) {
											case 7:
												if (new_bit) {
													fprintf(f, "\\ul ");
												} else {
													fprintf(f, "\\ulnone ");
												}
												break;
											case 6:
												if (new_bit) {
													fprintf(f, "\\b ");
												} else {
													fprintf(f, "\\b0 ");
												}
												break;
											case 5:
												if (new_bit) {
													fprintf(f, "{\\colortbl;\\red0\\green0\\blue0;\\red255\\green255\\blue255;}\\cb1\\cf2 ");
												} else {
													fprintf(f, "{\\colortbl;\\red0\\green0\\blue0;\\red255\\green255\\blue255;}\\cb2\\cf1 ");
												}
												break;
											case 4:
												if (new_bit) {
													fprintf(f, "\\i ");
												} else {
													fprintf(f, "\\i0 ");
												}
												break;
											case 3:
												if (new_bit) {
													fprintf(f, "\\outl\\strokewidth60 ");
												} else {
													fprintf(f, "\\outl0\\strokewidth0 ");
												}
												break;
											case 2:
												if (new_bit) {
													fprintf(f, "\\super ");
												} else {
													fprintf(f, "\\nosupersub ");
												}
												break;
											case 1:
												if (new_bit) {
													fprintf(f, "\\sub ");
												} else {
													fprintf(f, "\\nosupersub ");
												}
												break;
										}
									}
								}
							}
						}
						style = new_style;
					}
					j += 3;
					continue;
				}
				case 0x08:
				case 0x18:
					// Unknown Escape 0x08/0x18 (V1.1 only)
					debug_printf("<<<Unknown Escape 0x08/0x18>>>");
					j += 19;
					continue;
				case 0xF5:
					// Unknown Escape 0xF5 (V1.1 only)
					debug_printf("<<<Unknown Escape 0xF5>>>");
					j += 10;
					continue;
				case '{':
				case '}':
					if (print_rtf) {
						fprintf(f, "\\%c", c);
						continue;
					} else {
						break;
					}

			}
			fprintf(f, "%c", c);
		}
		payload += gross_size;
		debug_printf("<<<New Page>>>");
	}

	if (print_rtf) {
		fprintf(f, "}");
	}

	fclose(f);
	return 0;
}