From e2952dfaff67f3641d3a6d3226753356170ff808 Mon Sep 17 00:00:00 2001
From: Denys Vlasenko <vda.linux@googlemail.com>
Date: Sat, 8 Jan 2022 22:42:35 +0100
Subject: [PATCH] awk: input numbers are never octal or hex (only program
 consts can be)

function                                             old     new   delta
next_token                                           825     930    +105
getvar_i                                             114     129     +15
nextchar                                              49      53      +4
my_strtod                                            138       -    -138
------------------------------------------------------------------------------
(add/remove: 0/1 grow/shrink: 3/0 up/down: 124/-138)          Total: -14 bytes

Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
---
 editors/awk.c       | 29 ++++++++++++++++++++++-------
 testsuite/awk.tests | 12 +++++++++++-
 2 files changed, 33 insertions(+), 8 deletions(-)

diff --git a/editors/awk.c b/editors/awk.c
index f6314ac72..079d0bde5 100644
--- a/editors/awk.c
+++ b/editors/awk.c
@@ -848,7 +848,7 @@ static char *nextword(char **s)
 static char nextchar(char **s)
 {
 	char c, *pps;
-
+ again:
 	c = *(*s)++;
 	pps = *s;
 	if (c == '\\')
@@ -859,8 +859,11 @@ static char nextchar(char **s)
 	 */
 	if (c == '\\' && *s == pps) { /* unrecognized \z? */
 		c = *(*s); /* yes, fetch z */
-		if (c)
-			(*s)++; /* advance unless z = NUL */
+		if (c) { /* advance unless z = NUL */
+			(*s)++;
+			if (c == '\n') /* \<newline>? eat it */
+				goto again;
+		}
 	}
 	return c;
 }
@@ -882,7 +885,13 @@ static ALWAYS_INLINE int isalnum_(int c)
 static double my_strtod(char **pp)
 {
 	char *cp = *pp;
-	if (ENABLE_DESKTOP && cp[0] == '0') {
+	return strtod(cp, pp);
+}
+#if ENABLE_DESKTOP
+static double my_strtod_or_hexoct(char **pp)
+{
+	char *cp = *pp;
+	if (cp[0] == '0') {
 		/* Might be hex or octal integer: 0x123abc or 07777 */
 		char c = (cp[1] | 0x20);
 		if (c == 'x' || isdigit(cp[1])) {
@@ -901,6 +910,9 @@ static double my_strtod(char **pp)
 	}
 	return strtod(cp, pp);
 }
+#else
+# define my_strtod_or_hexoct(p) my_strtod(p)
+#endif
 
 /* -------- working with variables (set/get/copy/etc) -------- */
 
@@ -1014,6 +1026,7 @@ static double getvar_i(var *v)
 		if (s && *s) {
 			debug_printf_eval("getvar_i: '%s'->", s);
 			v->number = my_strtod(&s);
+			/* ^^^ hex/oct NOT allowed here! */
 			debug_printf_eval("%f (s:'%s')\n", v->number, s);
 			if (v->type & VF_USER) {
 //TODO: skip_spaces() also skips backslash+newline, is it intended here?
@@ -1125,10 +1138,10 @@ static uint32_t next_token(uint32_t expected)
 		if (*p == '\0') {
 			tc = TC_EOF;
 			debug_printf_parse("%s: token found: TC_EOF\n", __func__);
-		} else if (*p == '\"') {
+		} else if (*p == '"') {
 			/* it's a string */
 			char *s = t_string = ++p;
-			while (*p != '\"') {
+			while (*p != '"') {
 				char *pp;
 				if (*p == '\0' || *p == '\n')
 					syntax_error(EMSG_UNEXP_EOS);
@@ -1166,7 +1179,8 @@ static uint32_t next_token(uint32_t expected)
 		} else if (*p == '.' || isdigit(*p)) {
 			/* it's a number */
 			char *pp = p;
-			t_double = my_strtod(&pp);
+			t_double = my_strtod_or_hexoct(&pp);
+			/* ^^^ awk only allows hex/oct consts in _program_, not in _input_ */
 			p = pp;
 			if (*p == '.')
 				syntax_error(EMSG_UNEXP_TOKEN);
@@ -3503,6 +3517,7 @@ static var *evaluate(node *op, var *res)
 				i = (Ld == 0);
 				break;
 			}
+			debug_printf_eval("COMPARE result: %d\n", (i == 0) ^ (opn & 1));
 			setvar_i(res, (i == 0) ^ (opn & 1));
 			break;
 		}
diff --git a/testsuite/awk.tests b/testsuite/awk.tests
index bcaafe8fd..93e25d8c1 100755
--- a/testsuite/awk.tests
+++ b/testsuite/awk.tests
@@ -102,9 +102,13 @@ testing "awk unused function args are evaluated" \
 optional DESKTOP
 testing "awk hex const 1" "awk '{ print or(0xffffffff,1) }'" "4294967295\n" "" "\n"
 testing "awk hex const 2" "awk '{ print or(0x80000000,1) }'" "2147483649\n" "" "\n"
-testing "awk oct const"   "awk '{ print or(01234,1) }'"      "669\n"         "" "\n"
+testing "awk oct const"   "awk '{ print or(01234,1) }'"      "669\n"        "" "\n"
 SKIP=
 
+# check that "hex/oct integer" heuristic doesn't kick in on input
+# (must be done only when parsing program text)
+testing "awk input is never oct" "awk '{ print \$1, \$1+1 }'" "011 12\n"    "" "011\n"
+
 # check that "hex/oct integer" heuristic doesn't kick in on 00NN.NNN
 testing "awk floating const with leading zeroes" \
 	"awk '{ printf \"%f %f\n\", \"000.123\", \"009.123\" }'" \
@@ -469,4 +473,10 @@ testing 'awk printf %% prints one %' \
 	"%\n" \
 	'' ''
 
+testing 'awk backslash+newline eaten with no trace' \
+	"awk 'BEGIN { printf \"Hello\\
+ world\n\" }'" \
+	"Hello world\n" \
+	'' ''
+
 exit $FAILCOUNT