initial commit

1 files changed, 308 insertions, 0 deletions

diff --git a/atrsize.c b/atrsize.c
new file mode 100644
index 0000000..5571a02
--- /dev/null
+++ b/atrsize.c
@@ -0,0 +1,308 @@
+#include <stdio.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <unistd.h>
+#include <stdlib.h>
+#include <errno.h>
+#include <string.h>
+
+/* FIXME: This code is terrible.
+	I should have written an ATR library for atrsize, atr2xfd, and xfd2atr
+	to use, instead of the copy/paste mess I've created. */
+
+#ifndef VERSION
+#define VERSION "???"
+#endif
+
+#define SELF "atrsize"
+#define USAGE \
+	SELF " v" VERSION " by B. Watson (WTFPL)\n" \
+	"Usage: " SELF " -[bB] image.atr [sectors]\n" \
+	"  -b  Create image.atr as a new, blank, single-density image\n" \
+	"  -B  Create image.atr as a new, blank, double-density image\n" \
+	"Original image.atr is backed up as image.atr~\n" \
+	"Without [sectors], size is rounded up to next 'standard' size\n"
+
+char *usage = USAGE;
+
+int main(int argc, char **argv) {
+	struct stat st;
+	int filesize = 0;
+	int headersize = 0;
+	int blank = 0;
+	int len, sec;
+	unsigned int secsize, seccount, paras, newseccount = 0, last_data_sec = 0;
+	char *newsize, infile[4096], *outfile;
+	unsigned char buf[384];
+	FILE *in, *out;
+
+	if(argc < 2 || argc > 4) {
+		fprintf(stderr, usage);
+		exit(1);
+	}
+
+	if(strcmp(argv[1], "-b") == 0) {
+		blank = 128;
+		argv++;
+		argc--;
+	} else if(strcmp(argv[1], "-B") == 0) {
+		blank = 256;
+		argv++;
+		argc--;
+	}
+
+	newsize = argv[2];
+
+	outfile = argv[1];
+	strcpy(infile, outfile);
+	if( !(in = fopen(infile, "rb")) ) {
+		if(!blank) {
+			fprintf(stderr,
+					SELF ": %s: %s\n", infile, strerror(errno));
+			exit(1);
+		}
+
+		fprintf(stderr,
+				SELF ": %s does not exist, creating blank image\n", infile);
+
+		secsize = blank;
+		seccount = 720;
+
+		memset(buf, 0, 16);
+
+		buf[0] = 0x96;
+		buf[1] = 0x02;
+		buf[4] = secsize & 0xff;
+		buf[5] = (secsize >> 8) & 0xff;
+
+		filesize = headersize = 128 * 720 + (secsize - 128) * 717;
+		newseccount = seccount = 720;
+
+		paras = headersize / 16;
+		buf[2] = paras & 0xff;
+		buf[3] = (paras >> 8) & 0xff;
+		buf[6] = (paras >> 16) & 0xff;
+	}
+
+	if(in) {
+		if(blank) {
+			fprintf(stderr,
+					SELF ": won't create blank image %s: file exists\n", infile);
+			exit(1);
+		}
+
+		if(fstat(fileno(in), &st)) {
+			fprintf(stderr, "Can't determine size of %s: %s\n",
+					infile, strerror(errno));
+			exit(1);
+		} else {
+			filesize = st.st_size - 16;
+			if(filesize < 384) {
+				fprintf(stderr,
+						SELF ": %s is too small to be a valid ATR image\n",
+						infile);
+				exit(1);
+			}
+		}
+
+		if(fread(buf, 1, 16, in) != 16) {
+			fprintf(stderr, SELF ": %s: %s\n", infile, strerror(errno));
+			exit(1);
+		}
+	}
+
+	if( !(buf[0] == 0x96 && buf[1] == 0x02) ) {
+		fprintf(stderr,
+				SELF ": (fatal) %s not an ATR file (no NICKATARI signature)!\n",
+				infile);
+		exit(2);
+	}
+
+	secsize = buf[4] + (buf[5] << 8);
+
+	if( !(secsize == 128 || secsize == 256) ) {
+		fprintf(stderr,
+				SELF ": (fatal) %s has invalid sector size %d\n",
+				infile, secsize);
+		exit(2);
+	}
+
+	paras = buf[2] + (buf[3] << 8) + (buf[6] << 16);
+	headersize = paras * 16;
+
+	if(filesize && (filesize != headersize)) {
+		fprintf(stderr,
+				SELF ": warning: %s file size (%d bytes) doesn't agree with "
+				"ATR header (%d bytes). File may be truncated or corrupt.\n",
+				infile,
+				filesize,
+				headersize);
+	}
+
+	if(secsize == 128) {
+		fprintf(stderr, SELF ": single density image (128 bytes/sector)\n");
+		seccount = filesize / secsize;
+	} else {
+		fprintf(stderr, SELF ": double density image (256 bytes/sector)\n");
+		seccount = (filesize - 128 * 3) / secsize + 3;
+	}
+
+	newseccount = seccount;
+	if(newsize == NULL) {
+		/* figure out appropriate new size for this image */
+		if(secsize == 128) {
+			if(seccount < 720)
+				newseccount = 720;
+			else if(seccount > 720 && seccount < 1040)
+				newseccount = 1040;
+			else if(seccount >= 1040) {
+				fprintf(stderr, SELF ": must specify a sector count "
+						"for SD images >= 1040 sectors.\n");
+				exit(1);
+			}
+		} else {
+			if(seccount < 720)
+				newseccount = 720;
+			else if(seccount > 720 && seccount < 1440)
+				newseccount = 1440;
+			else if(seccount >= 1440) {
+				fprintf(stderr, SELF ": must specify a sector count "
+						"for DD images >= 1440 sectors.\n");
+				exit(1);
+			}
+		}
+
+		/*
+		if(in) {
+			if(newseccount == seccount) {
+				fprintf(stderr,
+						SELF ": image is already %d sectors, nothing to do\n", seccount);
+				exit(0);
+			} else if(!newseccount) {
+				fprintf(stderr,
+						SELF ": image is already standard size, nothing to do\n");
+				exit(0);
+			}
+		}
+		*/
+	} else {
+		newseccount = atoi(newsize);
+		if(newseccount < 3 || newseccount > 65535) {
+			fprintf(stderr,
+					SELF ": invalid sector count (must be 3 - 65535)\n");
+			exit(1);
+		}
+	}
+
+	if(newseccount < 368) {
+		fprintf(stderr, SELF ": warning: "
+				"Output image will not have Atari/MyDOS directory sectors.\n");
+	}
+
+	/* fix up ATR header */
+	if(secsize == 128)
+		headersize = secsize * newseccount;
+	else
+		headersize = (128 * 3) + (newseccount - 3) * secsize;
+
+	paras = headersize / 16;
+	buf[2] = paras & 0xff;
+	buf[3] = (paras >> 8) & 0xff;
+	buf[6] = (paras >> 16) & 0xff;
+
+	if(in) {
+		/* make backup file */
+		len = strlen(infile);
+		infile[len] = '~';
+		infile[len + 1] = '\0';
+
+		unlink(infile);
+		if(link(outfile, infile)) {
+			fprintf(stderr, SELF ": can't create %s: %s\n",
+					infile, strerror(errno));
+			exit(1);
+		}
+
+		if(unlink(outfile)) {
+			fprintf(stderr, SELF ": can't delete %s: %s\n",
+					outfile, strerror(errno));
+			exit(1);
+		}
+	}
+
+	if( !(out = fopen(outfile, "wb")) ) {
+		fprintf(stderr, SELF ": %s: %s\n", outfile, strerror(errno));
+		exit(1);
+	}
+
+	/* write ATR header */
+	if(fwrite(buf, 1, 16, out) != 16) {
+		fprintf(stderr, SELF ": %s: %s\n", outfile, strerror(errno));
+		exit(1);
+	}
+
+	/* read first 3 sectors (always present, always SD) */
+	if(in) {
+		if(fread(buf, 1, 384, in) != 384) {
+			fprintf(stderr, SELF ": %s: %s\n", infile, strerror(errno));
+			exit(1);
+		}
+	} else {
+		memset(buf, 0, 384);
+	}
+
+	/* write first 3 sectors */
+	if(fwrite(buf, 1, 384, out) != 384) {
+		fprintf(stderr, SELF ": %s: %s\n", outfile, strerror(errno));
+		exit(1);
+	}
+
+	for(sec = 4; (sec <= seccount) && (sec <= newseccount); sec++) {
+		int i, has_data = 0;
+
+		if(in) {
+			if(fread(buf, 1, secsize, in) != secsize) {
+				fprintf(stderr, SELF ": %s: %s\n", infile, strerror(errno));
+				exit(1);
+			}
+		}
+
+		for(i=0; i<secsize; i++)
+			has_data |= buf[i];
+
+		if(has_data)
+			last_data_sec = sec;
+
+		if(fwrite(buf, 1, secsize, out) != secsize) {
+			fprintf(stderr, SELF ": %s: %s\n", outfile, strerror(errno));
+			exit(1);
+		}
+	}
+
+	if(last_data_sec)
+		fprintf(stderr, SELF ": last non-empty sector was %d\n", last_data_sec);
+	else
+		fprintf(stderr, SELF ": image is blank (no data)\n");
+
+	if(newseccount < seccount) {
+		fprintf(stderr, SELF ": %s truncated to %d sectors, OK\n",
+				outfile, newseccount);
+	} else if(newseccount == seccount) {
+		fprintf(stderr, SELF ": %s rewritten at %d sectors, OK\n",
+				outfile, newseccount);
+	} else {
+		memset(buf, 0, secsize);
+		for( ; sec <= newseccount; sec++) {
+			if(fwrite(buf, 1, secsize, out) != secsize) {
+				fprintf(stderr, SELF ": %s: %s\n", outfile, strerror(errno));
+				exit(1);
+			}
+		}
+		fprintf(stderr, SELF ": %s extended to %d sectors, OK\n",
+				outfile, newseccount);
+	}
+
+	if(in) fclose(in);
+	fclose(out);
+	exit(0);
+}