aux/txt2uimage: helper for generating uimage script files

sys/src/cmd/aux/mkfile

@@ -43,6 +43,7 @@ TARG=\
 	tablet\
 	timesync\
 	trampoline\
+	txt2uimage\
 	unbflz\
 	usage\
 	write\

sys/src/cmd/aux/txt2uimage.c

@@ -0,0 +1,108 @@
+#include <u.h>
+#include <libc.h>
+#include <flate.h>
+
+int infd, outfd;
+ulong dcrc;
+ulong *tab;
+uchar buf[65536];
+
+enum {
+	IH_TYPE_SCRIPT		= 6,
+};
+
+void
+put(uchar *p, u32int v)
+{
+	*p++ = v >> 24;
+	*p++ = v >> 16;
+	*p++ = v >> 8;
+	*p = v;
+}
+
+void
+usage(void)
+{
+	fprint(2, "usage: %s a.out\n", argv0);
+	exits("usage");
+}
+
+void
+block(int n)
+{
+	int rc;
+
+	rc = readn(infd, buf, n);
+	if(rc < 0) sysfatal("read: %r");
+	if(rc < n) sysfatal("input file truncated");
+	if(write(outfd, buf, n) < 0) sysfatal("write: %r");
+	dcrc = blockcrc(tab, dcrc, buf, n);
+}
+
+void
+copy(int n)
+{
+	int i;
+
+	for(i = sizeof(buf) - 1; i < n; i += sizeof(buf))
+		block(sizeof(buf));
+	i = n & sizeof(buf) - 1;
+	if(i > 0)
+		block(i);
+}
+
+void
+main(int argc, char **argv)
+{
+	uchar header[64];
+	char *ofile;
+	Dir *dir;
+
+	ofile = nil;
+	ARGBEGIN {
+	case 'o': ofile = strdup(EARGF(usage())); break;
+	default: usage();
+	} ARGEND;
+
+	if(argc == 0)
+		infd = 0;
+	else {
+		if(argc != 1) usage();
+		infd = open(argv[0], OREAD);
+		if(infd < 0) sysfatal("infd: %r");
+	}
+	dir = dirfstat(infd);
+	if(dir == nil) sysfatal("stat: %r");
+	if(dir->length > 0xFFFFFFFF-8) sysfatal("file too big");
+	if(ofile == nil) ofile = smprint("%s.u", dir->name);
+	outfd = create(ofile, OWRITE|OTRUNC, 0666);
+	if(outfd < 0) sysfatal("create: %r");
+	
+	tab = mkcrctab(0xEDB88320);	
+	seek(outfd, sizeof(header), 0);
+	put(buf+0, dir->length);
+	put(buf+4, 0);
+	dcrc = blockcrc(tab, 0, buf, 8);
+	if(write(outfd, buf, 8) != 8) sysfatal("write: %r");
+	copy(dir->length);
+
+	memset(header, 0, sizeof(header));
+	put(&header[0], 0x27051956); /* magic */
+	put(&header[8], time(0)); /* time */
+	put(&header[12], 8+dir->length); /* image size */
+	put(&header[16], 0); /* load address */
+	put(&header[20], 0); /* entry point */
+	put(&header[24], dcrc); /* data crc */
+	header[28] = 0;
+	header[29] = 0;
+	header[30] = IH_TYPE_SCRIPT;
+	header[31] = 0; /* compressed = no */
+	
+	strncpy((char*)&header[32], dir->name, sizeof(header)-32);
+	put(&header[4], blockcrc(tab, 0, header, sizeof(header)));
+	
+	seek(outfd, 0, 0);
+	if(write(outfd, header, sizeof(header)) < sizeof(header)) sysfatal("write: %r");
+	
+	exits(nil);
+}