sbase

commit ec02816d3edfbc4de55afca285eba3377cda2ab5
parent 93d017885224d0d4c6e3d97ac9241d52beba060c
Author: Tai Chi Minh Ralph Eastwood <tcmreastwood@gmail.com>
Date:   Tue, 10 Feb 2015 19:14:27 +0000

uuencode: add support for base64 and -o to stdout

Diffstat:
M
uudecode.c
 | 
132
+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++------------
M
uuencode.c
 | 
66
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++----

2 files changed, 175 insertions(+), 23 deletions(-)
diff --git a/uudecode.c b/uudecode.c
@@ -11,26 +11,38 @@
 #include "text.h"
 #include "util.h"
 
+static void uudecodeb64(FILE *, FILE *);
 static void uudecode(FILE *, FILE *);
-static void parseheader(FILE *, const char *, const char *, mode_t *, char **);
+static void parseheader(FILE *, const char *, char **, mode_t *, char **);
 static FILE *parsefile(const char *);
 
 static void
 usage(void)
 {
-	eprintf("usage: %s [file]\n", argv0);
+	eprintf("usage: %s [-m] [-o output] [file]\n", argv0);
 }
 
+static int mflag = 0;
+static int oflag = 0;
+
 int
 main(int argc, char *argv[])
 {
 	FILE *fp = NULL, *nfp = NULL;
-	char *fname;
+	char *fname, *header;
+	const char *ifname;
 	mode_t mode = 0;
+	void (*d) (FILE *, FILE *) = NULL;
+	char *ofname = NULL;
 
 	ARGBEGIN {
 	case 'm':
-		eprintf("-m not implemented\n");
+		mflag = 1; /* accepted but unused (autodetect file type) */
+		break;
+	case 'o':
+		oflag = 1;
+		ofname = EARGF(usage());
+		break;
 	default:
 		usage();
 	} ARGEND;
@@ -39,20 +51,31 @@ main(int argc, char *argv[])
 		usage();
 
 	if (argc == 0) {
-		parseheader(stdin, "<stdin>", "begin ", &mode, &fname);
-		if (!(nfp = parsefile(fname)))
-			eprintf("fopen %s:", fname);
-		uudecode(stdin, nfp);
+		fp = stdin;
+		ifname = "<stdin>";
 	} else {
 		if (!(fp = fopen(argv[0], "r")))
 			eprintf("fopen %s:", argv[0]);
-		parseheader(fp, argv[0], "begin ", &mode, &fname);
-		if (!(nfp = parsefile(fname)))
-			eprintf("fopen %s:", fname);
-		uudecode(fp, nfp);
+		ifname = argv[0];
 	}
 
-	if (chmod(fname, mode) < 0)
+	parseheader(fp, ifname, &header, &mode, &fname);
+
+	if (!strncmp(header, "begin", sizeof("begin")))
+		d = uudecode;
+	else if (!strncmp(header, "begin-base64", sizeof("begin-base64")))
+		d = uudecodeb64;
+	else
+		eprintf("unknown header %s:", header);
+
+	if (oflag)
+		fname = ofname;
+	if (!(nfp = parsefile(fname)))
+		eprintf("fopen %s:", fname);
+
+	d(fp, nfp);
+
+	if (nfp != stdout && chmod(fname, mode) < 0)
 		eprintf("chmod %s:", fname);
 	if (fp)
 		fclose(fp);
@@ -68,7 +91,7 @@ parsefile(const char *fname)
 	struct stat st;
 	int ret;
 
-	if (strcmp(fname, "/dev/stdout") == 0)
+	if (strcmp(fname, "/dev/stdout") == 0 || strcmp(fname, "-") == 0)
 		return stdout;
 	ret = lstat(fname, &st);
 	/* if it is a new file, try to open it */
@@ -87,9 +110,10 @@ tropen:
 }
 
 static void
-parseheader(FILE *fp, const char *s, const char *header, mode_t *mode, char **fname)
+parseheader(FILE *fp, const char *s, char **header, mode_t *mode,
+	    char **fname)
 {
-	char bufs[PATH_MAX + 11]; /* len header + mode + maxname */
+	char bufs[PATH_MAX + 18]; /* len header + mode + maxname */
 	char *p, *q;
 	size_t n;
 
@@ -101,9 +125,12 @@ parseheader(FILE *fp, const char *s, const char *header, mode_t *mode, char **fn
 	if (!(p = strchr(bufs, '\n')))
 		eprintf("header string too long or non-newline terminated file\n");
 	p = bufs;
-	if (strncmp(bufs, header, strlen(header)) != 0)
-		eprintf("malformed header prefix\n");
-	p += strlen(header);
+	if (!(q = strchr(p, ' ')))
+		eprintf("malformed mode string in header\n");
+	*header = bufs;
+	*q++ = '\0';
+	p = q;
+	/* now header should be null terminated, q points to mode */
 	if (!(q = strchr(p, ' ')))
 		eprintf("malformed mode string in header\n");
 	*q++ = '\0';
@@ -115,6 +142,73 @@ parseheader(FILE *fp, const char *s, const char *header, mode_t *mode, char **fn
 	if (n > 0)
 		*fname = q;
 }
+static const char b64dt[] = {
+	-1,-1,-1,-1,-1,-1,-1,-1,-1,-2,-2,-2,-2,-2,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,
+	-1,-1,-1,-1,-1,-1,-1,-1,-2,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,62,-1,-1,-1,63,
+	52,53,54,55,56,57,58,59,60,61,-1,-1,-1,0,-1,-1,-1,0,1,2,3,4,5,6,
+	7,8,9,10,11,12,13,14,15,16,17,18,19,20,21,22,23,24,25,-1,-1,-1,-1,-1,
+	-1,26,27,28,29,30,31,32,33,34,35,36,37,38,39,40,41,42,43,44,45,46,47,48,
+	49,50,51,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,
+	-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,
+	-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,
+	-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,
+	-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,
+	-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,
+};
+
+static void
+uudecodeb64(FILE *fp, FILE *outfp)
+{
+	char bufb[60], *pb;
+	char out[45], *po;
+	size_t n;
+	int b = 0, e, t = 0;
+	unsigned char b24[3] = {0, 0, 0};
+
+	while ((n = fread(bufb, 1, sizeof(bufb), fp))) {
+		for (pb = bufb, po = out; pb < bufb + n; pb++) {
+			if (*pb == '=') {
+				if (b == 0 || t) {
+					/* footer size is ==== is 4 */
+					if (++t < 4)
+						continue;
+					else
+						return;
+				} else if (b == 1) {
+					eprintf("unexpected \"=\" appeared.");
+				} else if (b == 2) {
+					*po++ = b24[0];
+					fwrite(out, 1, (po - out), outfp);
+				} else if (b == 3) {
+					*po++ = b24[0];
+					*po++ = b24[1];
+					fwrite(out, 1, (po - out), outfp);
+				}
+			}
+			if ((e = b64dt[(int)*pb]) == -1) {
+				eprintf("invalid byte \"%c\"", *pb);
+			} else if (e == -2) /* whitespace */
+				continue;
+			switch (b) {
+				case 0: b24[0] |= e << 2; break;
+				case 1: b24[0] |= (e >> 4) & 0x3;
+				        b24[1] |= (e & 0xf) << 4; break;
+				case 2: b24[1] |= (e >> 2) & 0xf;
+				        b24[2] |= (e & 0x3) << 6; break;
+				case 3: b24[2] |= e; break;
+			}
+			if (++b == 4) {
+				*po++ = b24[0];
+				*po++ = b24[1];
+				*po++ = b24[2];
+				b24[0] = b24[1] = b24[2] = 0;
+				b = 0;
+			}
+		}
+		fwrite(out, 1, (po - out), outfp);
+	}
+	eprintf("invalid uudecode footer \"====\" not found\n");
+}
 
 static void
 uudecode(FILE *fp, FILE *outfp)
diff --git a/uuencode.c b/uuencode.c
@@ -4,15 +4,19 @@
 #include <sys/stat.h>
 #include <sys/types.h>
 #include <unistd.h>
+#include <assert.h>
 
 #include "util.h"
 
+static int mflag = 0;
+
+static void uuencodeb64(FILE *, const char *, const char *);
 static void uuencode(FILE *, const char *, const char *);
 
 static void
 usage(void)
 {
-	eprintf("usage: %s [file] name\n", argv0);
+	eprintf("usage: %s [-m] [file] name\n", argv0);
 }
 
 int
@@ -22,7 +26,8 @@ main(int argc, char *argv[])
 
 	ARGBEGIN {
 	case 'm':
-		eprintf("-m not implemented\n");
+		mflag = 1;
+		break;
 	default:
 		usage();
 	} ARGEND;
@@ -31,16 +36,69 @@ main(int argc, char *argv[])
 		usage();
 
 	if (argc == 1) {
-		uuencode(stdin, argv[0], "<stdin>");
+		if (mflag)
+			uuencodeb64(stdin, argv[0], "<stdin>");
+		else
+			uuencode(stdin, argv[0], "<stdin>");
 	} else {
 		if (!(fp = fopen(argv[0], "r")))
 			eprintf("fopen %s:", argv[0]);
-		uuencode(fp, argv[1], argv[0]);
+		if (mflag)
+			uuencodeb64(fp, argv[1], argv[0]);
+		else
+			uuencode(fp, argv[1], argv[0]);
 		fclose(fp);
 	}
 	return 0;
 }
 
+static const char b64et[] = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/";
+/* much faster */
+static unsigned int
+b64e(unsigned char b[2])
+{
+	unsigned int o = 0;
+	unsigned int p = b[2] | (b[1] << 8) | (b[0] << 16);
+	o = b64et[p & 0x3f]; p >>= 6;
+	o = (o << 8) | b64et[p & 0x3f]; p >>= 6;
+	o = (o << 8) | b64et[p & 0x3f]; p >>= 6;
+	o = (o << 8) | b64et[p & 0x3f];
+	return o;
+}
+
+static void
+uuencodeb64(FILE *fp, const char *name, const char *s)
+{
+	struct stat st;
+	ssize_t n, m = 0;
+	unsigned char buf[45], *pb;
+	unsigned int out[sizeof(buf)/3 + 1], *po;
+	if (fstat(fileno(fp), &st) < 0)
+		eprintf("fstat %s:", s);
+	printf("begin-base64 %o %s\n", st.st_mode & 0777, name);
+	/* write line by line */
+	while ((n = fread(buf, 1, sizeof(buf), fp))) {
+		/* clear old buffer if converting with non-multiple of 3 */
+		if (n != sizeof(buf) && (m = n % 3) != 0) {
+			buf[n] = '\0'; /* m == 2 */
+			if (m == 1) buf[n+1] = '\0'; /* m == 1 */
+		}
+		for (pb = buf, po = out; pb < buf + n; pb += 3)
+			*po++ = b64e(pb);
+		if (m != 0) {
+			unsigned int mask = 0xffffffff, dest = 0x3d3d3d3d;
+			/* m==2 -> 0x00ffffff; m==1 -> 0x0000ffff */
+			mask >>= ((3-m) << 3); 
+			po[-1] = (po[-1] & mask) | (dest & ~mask);
+		}
+		*po++ = '\n';
+		fwrite(out, 1, (po - out) * sizeof(unsigned int) - 3, stdout);
+	}
+	if (ferror(fp))
+		eprintf("'%s' read error:", s);
+	puts("====");
+}
+
 static void
 uuencode(FILE *fp, const char *name, const char *s)
 {