← Commit list

a4f331d3c

Mike Frysinger

2009-04-07

FAILED Duration: 31s

Subject

implement support for parameter substitution via #/% operators

Binary

No binary (build failed)

Architecture & Compiler Flags

Architecture: x86_64-linux-gnu Compiler: gcc (Ubuntu 11.4.0-1ubuntu1~22.04.3) 11.4.0

—

Build Log

(log yok)

Commit Diff GitHub →

shell/Kbuild +1 -1 shell/hush.c +41 -24 shell/hush_test/hush-vars/var_posix1.right +17 -0 shell/hush_test/hush-vars/var_posix1.tests +21 -0 shell/match.c +141 -0 shell/match.h +22 -0

shell/Kbuild+1 -1

@@ -6,7 +6,7 @@

	lib-y:=
	lib-$(CONFIG_ASH) += ash.o ash_ptr_hack.o
-	lib-$(CONFIG_HUSH) += hush.o
+	lib-$(CONFIG_HUSH) += hush.o match.o
	lib-$(CONFIG_MSH) += msh.o
	lib-$(CONFIG_CTTYHACK) += cttyhack.o
	lib-$(CONFIG_SH_MATH_SUPPORT) += math.o

shell/hush.c+41 -24

@@ -43,7 +43,6 @@
	* Here Documents ( << word )
	* Functions
	* Tilde Expansion
-	* Parameter Expansion for substring processing ${var#word} ${var%word}
	*
	* Bash stuff (maybe optionally enable?):
	* &> and >& redirection of stdout+stderr
@@ -76,6 +75,7 @@
	#include <fnmatch.h>
	#endif
	#include "math.h"
+	#include "match.h"

	#ifdef WANT_TO_TEST_NOMMU
	# undef BB_MMU
@@ -1667,8 +1667,9 @@ static int expand_vars_to_list(o_string output, int n, char arg, char or_mask)
	char first_ch, ored_ch;
	int i;
	const char *val;
-	char *p;
+	char dyn_val, p;

+	dyn_val = NULL;
	ored_ch = 0;

	debug_printf_expand("expand_vars_to_list: arg '%s'\n", arg);
@@ -1844,7 +1845,7 @@ static int expand_vars_to_list(o_string output, int n, char arg, char or_mask)
	++var;
	} else {
	/* maybe handle parameter expansion */
-	exp_off = strcspn(var, ":-=+?");
+	exp_off = strcspn(var, ":-=+?%#");
	if (!var[exp_off])
	exp_off = 0;
	if (exp_off) {
@@ -1873,29 +1874,45 @@ static int expand_vars_to_list(o_string output, int n, char arg, char or_mask)
	val = utoa(val ? strlen(val) : 0);
	debug_printf_expand("%s\n", val);
	} else if (exp_off) {
-	/* we need to do an expansion */
-	int exp_test = (!val \|\| (exp_null && !val[0]));
-	if (exp_op == '+')
-	exp_test = !exp_test;
-	debug_printf_expand("expand: op:%c (null:%s) test:%i\n", exp_op,
-	exp_null ? "true" : "false", exp_test);
-	if (exp_test) {
-	if (exp_op == '?')
-	maybe_die(var, *exp_word ? exp_word : "parameter null or not set");
+	if (exp_op == '%' \|\| exp_op == '#') {
+	/* we need to do a pattern match */
+	bool zero;
+	char *loc;
+	scan_t scan = pick_scan(exp_op, *exp_word, &zero);
+	if (exp_op == exp_word) / ## or %% */
+	++exp_word;
+	val = dyn_val = xstrdup(val);
+	loc = scan(dyn_val, exp_word, zero);
+	if (zero)
+	val = loc;
	else
-	val = exp_word;
-
-	if (exp_op == '=') {
-	if (isdigit(var[0]) \|\| var[0] == '#') {
-	maybe_die(var, "special vars cannot assign in this way");
-	val = NULL;
-	} else {
-	char *new_var = xmalloc(strlen(var) + strlen(val) + 2);
-	sprintf(new_var, "%s=%s", var, val);
-	set_local_var(new_var, -1, 0);
+	*loc = '\0';
+	} else {
+	/* we need to do an expansion */
+	int exp_test = (!val \|\| (exp_null && !val[0]));
+	if (exp_op == '+')
+	exp_test = !exp_test;
+	debug_printf_expand("expand: op:%c (null:%s) test:%i\n", exp_op,
+	exp_null ? "true" : "false", exp_test);
+	if (exp_test) {
+	if (exp_op == '?')
+	maybe_die(var, *exp_word ? exp_word : "parameter null or not set");
+	else
+	val = exp_word;
+
+	if (exp_op == '=') {
+	if (isdigit(var[0]) \|\| var[0] == '#') {
+	maybe_die(var, "special vars cannot assign in this way");
+	val = NULL;
+	} else {
+	char *new_var = xmalloc(strlen(var) + strlen(val) + 2);
+	sprintf(new_var, "%s=%s", var, val);
+	set_local_var(new_var, -1, 0);
+	}
	}
	}
	}
+
	var[exp_off] = exp_save;
	}

@@ -1921,6 +1938,8 @@ static int expand_vars_to_list(o_string output, int n, char arg, char or_mask)
	if (val) {
	o_addQstr(output, val, strlen(val));
	}
+	free(dyn_val);
+	dyn_val = NULL;
	/* Do the check to avoid writing to a const string */
	if (*p != SPECIAL_VAR_SYMBOL)
	*p = SPECIAL_VAR_SYMBOL;
@@ -4428,7 +4447,6 @@ static int handle_dollar(o_string *as_string,
	break;
	}
	goto case_default;
-	#if 0 /* not implemented yet :( */
	case '#': /* remove prefix */
	case '%': /* remove suffix */
	if (expansion == 0) {
@@ -4437,7 +4455,6 @@ static int handle_dollar(o_string *as_string,
	break;
	}
	goto case_default;
-	#endif
	case '-': /* default value */
	case '=': /* assign default */
	case '+': /* alternative */

shell/hush_test/hush-vars/var_posix1.right+17 -0

@@ -0,0 +1,17 @@
+	abcdcd
+	abcdcd
+	abcdcd
+	cdcd
+	babcdcd
+	babcdcd
+	ababcdcd
+
+	ababcd
+	ababcd
+	ababcd
+	abab
+	ababcdc
+	ababcdc
+	ababcdcd
+
+	end

shell/hush_test/hush-vars/var_posix1.tests+21 -0

@@ -0,0 +1,21 @@
+	var=ababcdcd
+
+	echo ${var#ab}
+	echo ${var##ab}
+	echo ${var#a*b}
+	echo ${var##a*b}
+	echo ${var#?}
+	echo ${var##?}
+	echo ${var#*}
+	echo ${var##*}
+
+	echo ${var%cd}
+	echo ${var%%cd}
+	echo ${var%c*d}
+	echo ${var%%c*d}
+	echo ${var%?}
+	echo ${var%%?}
+	echo ${var%*}
+	echo ${var%%*}
+
+	echo end

shell/match.c+141 -0

@@ -0,0 +1,141 @@
+	/*
+	* ##/%% variable matching code ripped out of ash shell for code sharing
+	*
+	* Copyright (c) 1989, 1991, 1993, 1994
+	* The Regents of the University of California. All rights reserved.
+	*
+	* Copyright (c) 1997-2005 Herbert Xu <[email protected]>
+	* was re-ported from NetBSD and debianized.
+	*
+	* This code is derived from software contributed to Berkeley by
+	* Kenneth Almquist.
+	*
+	* Licensed under the GPL v2 or later, see the file LICENSE in this tarball.
+	*
+	* Original BSD copyright notice is retained at the end of this file.
+	*/
+
+	#ifdef STANDALONE
+	# include <stdbool.h>
+	# include <stdio.h>
+	# include <stdlib.h>
+	# include <string.h>
+	# include <unistd.h>
+	#else
+	# include "busybox.h"
+	#endif
+	#include <fnmatch.h>
+	#include "match.h"
+
+	#define pmatch(a, b) !fnmatch((a), (b), 0)
+
+	char scanleft(char string, char *pattern, bool zero)
+	{
+	char c;
+	char *loc = string;
+
+	do {
+	int match;
+	const char *s;
+
+	c = *loc;
+	if (zero) {
+	*loc = '\0';
+	s = string;
+	} else
+	s = loc;
+	match = pmatch(pattern, s);
+	*loc = c;
+
+	if (match)
+	return loc;
+
+	loc++;
+	} while (c);
+
+	return NULL;
+	}
+
+	char scanright(char string, char *pattern, bool zero)
+	{
+	char c;
+	char *loc = string + strlen(string);
+
+	while (loc >= string) {
+	int match;
+	const char *s;
+
+	c = *loc;
+	if (zero) {
+	*loc = '\0';
+	s = string;
+	} else
+	s = loc;
+	match = pmatch(pattern, s);
+	*loc = c;
+
+	if (match)
+	return loc;
+
+	loc--;
+	}
+
+	return NULL;
+	}
+
+	#ifdef STANDALONE
+	int main(int argc, char *argv[])
+	{
+	char *string;
+	char *op;
+	char *pattern;
+	bool zero;
+	char *loc;
+
+	int i;
+
+	if (argc == 1) {
+	puts(
+	"Usage: match <test> [test...]\n\n"
+	"Where a <test> is the form: <string><op><match>\n"
+	"This is to test the shell ${var#val} expression type.\n\n"
+	"e.g. `match 'abc#a*'` -> bc"
+	);
+	return 1;
+	}
+
+	for (i = 1; i < argc; ++i) {
+	size_t off;
+	scan_t scan;
+
+	printf("'%s': ", argv[i]);
+
+	string = strdup(argv[i]);
+	off = strcspn(string, "#%");
+	if (!off) {
+	printf("invalid format\n");
+	free(string);
+	continue;
+	}
+	op = string + off;
+	scan = pick_scan(op[0], op[1], &zero);
+	pattern = op + 1;
+	if (op[0] == op[1])
+	op[1] = '\0', ++pattern;
+	op[0] = '\0';
+
+	loc = scan(string, pattern, zero);
+
+	if (zero) {
+	printf("'%s'\n", loc);
+	} else {
+	*loc = '\0';
+	printf("'%s'\n", string);
+	}
+
+	free(string);
+	}
+
+	return 0;
+	}
+	#endif

shell/match.h+22 -0

@@ -0,0 +1,22 @@
+	/* match.h - interface to shell ##/%% matching code */
+
+	typedef char (scan_t)(char string, char match, bool zero);
+
+	char scanleft(char string, char *match, bool zero);
+	char scanright(char string, char *match, bool zero);
+
+	static inline scan_t pick_scan(char op1, char op2, bool *zero)
+	{
+	/* # - scanleft
+	* ## - scanright
+	* % - scanright
+	* %% - scanleft
+	*/
+	if (op1 == '#') {
+	*zero = true;
+	return op1 == op2 ? scanright : scanleft;
+	} else {
+	*zero = false;
+	return op1 == op2 ? scanleft : scanright;
+	}
+	}