btcs

commit f69017607010372aaecdf65e4aca6ed5b25bf846
parent 9005e5c975d57701622880ac9ff93fecf92f2e6b
Author: William Casarin <jb55@jb55.com>
Date:   Wed, 19 Jun 2019 00:36:33 -0700

decode: parse more bad inputs

it will try to parse until it can't any longer, and then it
will continue to print the remaining line.

This is useful for things like:

bitcoin-iterate -q --cache=cache --output=$'%os,%th' \
  --start 500000 --blockdir=/zbig/bitcoin2/blocks \
    | btcs -a -d \
    | awk -F, '!x[$1]++'

HASH160 data(20) EQUAL,2157b554dcfda405233906e461ee593875ae4b1b97615872db6a25130ecc1dd6
RETURN data(36),2157b554dcfda405233906e461ee593875ae4b1b97615872db6a25130ecc1dd6
DUP HASH160 data(20) EQUALVERIFY CHECKSIG,1024cb12a576b69defa67dbc2f1899700ab58e5ad3d5e058edefb907f59865bc
RETURN data(20),8662e51ae3e9a8a050dc958a95ea27015107388ba212e483755121427e7ba2b7
0 data(20),761619410d9f2a7fa69336583a0351dd86caf9ed2cee8765132a93caa44f77de
0 data(32),577819ae38ccd0d2b931aeec4f83801ad3c42b3158d4ceb4874f2ef482f1d805
RETURN data(17),af41a3eb6505c08003195be6affd3961e45278b45d58d0a427532eeb67501353

Signed-off-by: William Casarin <jb55@jb55.com>

Diffstat:
M
main.c
 | 
20
+++++++++++++-------
M
script.c
 | 
9
++++++---
M
util.c
 | 
21
++++++++++++---------
M
util.h
 | 
2
+-

4 files changed, 32 insertions(+), 20 deletions(-)
diff --git a/main.c b/main.c
@@ -125,15 +125,16 @@ static void fail(int err, const char *msg)
 }
 
 
-static int decompile(const char *str, int strlen, bool abbrev_data)
+static int decompile(const char *str, size_t *strlen, bool abbrev_data)
 {
 	static u8 buf[10000];
 
-	if (strlen % 2 != 0)
+	hex_decode(str, strlen, buf, sizeof(buf));
+
+	if (*strlen % 2 != 0)
 		return 0;
 
-	hex_decode(str, strlen, buf, sizeof(buf));
-	size_t nbytes = strlen / 2;
+	size_t nbytes = *strlen / 2;
 
 	script_print(buf, nbytes, abbrev_data);
 
@@ -203,14 +204,18 @@ int main(int argc, const char *argv[])
 	if (is_decompile) {
 		// we have stdin
 		char *line = NULL;
-		ssize_t len = 0;
+		ssize_t len = 0, prevlen;
 		size_t n;
 		int ok;
 		bool failed = false;
 
 		if (input == NULL) {
 			while ((len = getline(&line, &n, stdin)) != -1) {
-				ok = decompile(line, len-1, abbrev_data);
+				len--;
+				prevlen = len;
+				ok = decompile(line, (size_t*)&len, abbrev_data);
+
+				printf("%.*s\n", (int)(prevlen - len), line+len);
 
 				if (!ok) {
 					failed = true;
@@ -224,7 +229,8 @@ int main(int argc, const char *argv[])
 			if (!ok)
 				fail(4, "failed to read input arg (too big?)");
 
-			ok = decompile((const char *)buf, written, abbrev_data);
+			ok = decompile((const char *)buf, &written, abbrev_data);
+			printf("\n");
 
 			if (!ok) {
 				fprintf(stderr, "failed to decompile\n");
diff --git a/script.c b/script.c
@@ -755,24 +755,27 @@ void script_print(const u8 *script, size_t script_size, int abbrev_data) {
   static u8 tmpbuf[4096];
   const u8 *p = script;
   const u8 *top = script + script_size;
+  bool first = true;
 
   while (p < top) {
     enum opcode opcode;
     script_getop(&p, top, &opcode, tmpbuf, sizeof(tmpbuf), &len);
 
+    if (!first)
+	    putchar(' ');
+    first = false;
+
     if (is_push_data(opcode)) {
 	    if (abbrev_data)
 		    printf("data(%d)", len);
 	    else
 		    hex_print(tmpbuf, len);
-	    printf(" ");
     }
     else
-	    printf("%s ", op_name(opcode));
+	    printf("%s", op_name(opcode));
 
     len = 0;
   }
-  printf("\n");
 }
 
 void script_print_vals(struct stack *stack) {
diff --git a/util.c b/util.c
@@ -1,6 +1,7 @@
 
 #include "util.h"
 #include <errno.h>
+#include <assert.h>
 
 static bool char_to_hex(unsigned char *val, char c)
 {
@@ -19,22 +20,25 @@ static bool char_to_hex(unsigned char *val, char c)
 	return false;
 }
 
-bool hex_decode(const char *str, size_t slen, void *buf, size_t bufsize)
+bool hex_decode(const char *str, size_t *slen, void *buf, size_t bufsize)
 {
 	unsigned char v1, v2;
 	unsigned char *p = buf;
+	int len = 0;
 
-	while (slen > 1) {
-		if (!char_to_hex(&v1, str[0]) || !char_to_hex(&v2, str[1]))
-			return false;
-		if (!bufsize)
+	while (*slen > 1) {
+		if (!bufsize || !char_to_hex(&v1, str[0]) || !char_to_hex(&v2, str[1])) {
+			*slen = len;
 			return false;
+		}
 		*(p++) = (v1 << 4) | v2;
 		str += 2;
-		slen -= 2;
+		*slen -= 2;
 		bufsize--;
+		len += 2;
 	}
-	return slen == 0 && bufsize == 0;
+	*slen = len;
+	return *slen == 0 && bufsize == 0;
 }
 
 
@@ -109,13 +113,12 @@ ssize_t getline(char **lineptr, size_t *n, FILE *stream) {
 int read_arg_or_stdin(const char *arg, unsigned char *buf, size_t buflen,
 		      size_t *written)
 {
-	unsigned char dummy;
 	if (arg != NULL) {
 		unsigned char *p = buf;
 		bool done = false;
 		for (size_t i = 0; i < buflen; i++) {
 			*p = arg[i];
-			if (*p == 0 || !char_to_hex(&dummy, *p)) {
+			if (*p == 0 ) {
 				done = true;
 				break;
 			}
diff --git a/util.h b/util.h
@@ -11,7 +11,7 @@ typedef intptr_t ssize_t;
 
 
 int read_arg_or_stdin(const char *arg, unsigned char *buf, size_t buflen, size_t *written);
-bool hex_decode(const char *str, size_t slen, void *buf, size_t bufsize);
+bool hex_decode(const char *str, size_t *slen, void *buf, size_t bufsize);
 ssize_t getline(char **lineptr, size_t *n, FILE *stream);
 
 #endif /* UTIL_H */