This incorporates Posix math support into ash. The Posix math support
was written by Aaron Lehmann <aaronl@vitelus.com> for busybox. This
patch makes a few trivial changes to Aaron's code so that it can be
used (in theory) by the other shells as well...
-Erik
diff --git a/Makefile b/Makefile
index 7ee55f8..88a7aa0 100644
--- a/Makefile
+++ b/Makefile
@@ -247,7 +247,7 @@
trim.c unzip.c vdprintf.c verror_msg.c vperror_msg.c wfopen.c xfuncs.c \
xgetcwd.c xreadlink.c xregcomp.c interface.c remove_file.c last_char_is.c \
copyfd.c vherror_msg.c herror_msg.c herror_msg_and_die.c xgethostbyname.c \
-dirname.c make_directory.c create_icmp_socket.c
+dirname.c make_directory.c create_icmp_socket.c arith.c
LIBBB_OBJS=$(patsubst %.c,$(LIBBB)/%.o, $(LIBBB_CSRC))
LIBBB_CFLAGS = -I$(LIBBB)
ifneq ($(strip $(BB_SRC_DIR)),)
diff --git a/ash.c b/ash.c
index bb5bf36..9a5435e 100644
--- a/ash.c
+++ b/ash.c
@@ -51,9 +51,8 @@
#define ASH_ALIAS
/* If you need ash to act as a full Posix shell, with full math
- * support, enable this. This option needs some work, since it
- * doesn't compile right now... */
-#undef ASH_MATH_SUPPORT
+ * support, enable this. This adds a bit over 2k an x86 system. */
+#define ASH_MATH_SUPPORT
/* Getopts is used by shell procedures to parse positional parameters.
* You probably want to leave this disabled, and use the busybox getopt
@@ -80,6 +79,7 @@
#undef FNMATCH_BROKEN
#undef GLOB_BROKEN
#undef _GNU_SOURCE
+#undef __USE_GNU
#include <assert.h>
#include <ctype.h>
@@ -1562,8 +1562,10 @@
#endif
#ifdef ASH_MATH_SUPPORT
-/* The generated file arith.c has been snipped. If you want this
- * stuff back in, feel free to add it to your own copy. */
+/* The generated file arith.c has been replaced with a custom hand
+ * written implementation written by Aaron Lehmann <aaronl@vitelus.com>.
+ * This is now part of libbb, so that it can be used by all the shells
+ * in busybox. */
#define ARITH_NUM 257
#define ARITH_LPAREN 258
#define ARITH_RPAREN 259
@@ -1592,11 +1594,8 @@
static void expari (int);
/* From arith.y */
-static int arith (const char *);
+static long ash_arith(const char *p);
static int expcmd (int , char **);
-static void arith_lex_reset (void);
-static int yylex (void);
-
#endif
static char *trap[NSIG]; /* trap handler commands */
@@ -2173,52 +2172,22 @@
}
-#ifdef __STDC__
-static void
+static void
error(const char *msg, ...)
-#else
-static void
-error(va_alist)
- va_dcl
-#endif
{
-#ifndef __STDC__
- const char *msg;
-#endif
va_list ap;
-#ifdef __STDC__
va_start(ap, msg);
-#else
- va_start(ap);
- msg = va_arg(ap, const char *);
-#endif
exverror(EXERROR, msg, ap);
/* NOTREACHED */
va_end(ap);
}
-#ifdef __STDC__
static void
exerror(int cond, const char *msg, ...)
-#else
-static void
-exerror(va_alist)
- va_dcl
-#endif
{
-#ifndef __STDC__
- int cond;
- const char *msg;
-#endif
va_list ap;
-#ifdef __STDC__
va_start(ap, msg);
-#else
- va_start(ap);
- cond = va_arg(ap, int);
- msg = va_arg(ap, const char *);
-#endif
exverror(cond, msg, ap);
/* NOTREACHED */
va_end(ap);
@@ -4914,7 +4883,7 @@
removerecordregions(begoff);
if (quotes)
rmescapes(p+2);
- result = arith(p+2);
+ result = ash_arith(p+2);
snprintf(p, 12, "%d", result);
while (*p++)
@@ -11952,13 +11921,7 @@
trace(const char *fmt, ...)
{
va_list va;
-#ifdef __STDC__
va_start(va, fmt);
-#else
- char *fmt;
- va_start(va);
- fmt = va_arg(va, char *);
-#endif
if (tracefile != NULL) {
(void) vfprintf(tracefile, fmt, va);
if (strchr(fmt, '\n'))
@@ -12657,7 +12620,6 @@
return 0;
}
-
/*
* The "local" command.
*/
@@ -12916,7 +12878,7 @@
/*
* Copyright (c) 1999 Herbert Xu <herbert@debian.org>
* This file contains code for the times builtin.
- * $Id: ash.c,v 1.13 2001/07/26 05:58:40 russ Exp $
+ * $Id: ash.c,v 1.14 2001/07/30 21:41:37 andersen Exp $
*/
static int timescmd (int argc, char **argv)
{
@@ -12937,6 +12899,51 @@
}
+#ifdef ASH_MATH_SUPPORT
+/* The exp(1) builtin. */
+int expcmd(int argc, char **argv)
+{
+ const char *p;
+ char *concat;
+ char **ap;
+ long i;
+
+ if (argc > 1) {
+ p = argv[1];
+ if (argc > 2) {
+ /* concatenate arguments */
+ STARTSTACKSTR(concat);
+ ap = argv + 2;
+ for (;;) {
+ while (*p)
+ STPUTC(*p++, concat);
+ if ((p = *ap++) == NULL)
+ break;
+ STPUTC(' ', concat);
+ }
+ STPUTC('\0', concat);
+ p = grabstackstr(concat);
+ }
+ } else
+ p = "";
+
+ i = ash_arith(p);
+
+ printf("%ld\n", i);
+ return (! i);
+}
+
+static long ash_arith(const char *p)
+{
+ long i = arith(p);
+ if (i <0)
+ error("arith: syntax error: \"%s\"\n", p);
+ return i;
+}
+#endif
+
+
+
/*-
* Copyright (c) 1989, 1991, 1993, 1994
* The Regents of the University of California. All rights reserved.
diff --git a/include/libbb.h b/include/libbb.h
index 3cf932d..66acc22 100644
--- a/include/libbb.h
+++ b/include/libbb.h
@@ -212,6 +212,8 @@
char *concat_path_file(const char *path, const char *filename);
char *last_char_is(const char *s, int c);
+extern long arith (const char *startbuf);
+
typedef struct file_headers_s {
char *name;
char *link_name;
diff --git a/libbb/arith.c b/libbb/arith.c
new file mode 100644
index 0000000..c7a3cf9
--- /dev/null
+++ b/libbb/arith.c
@@ -0,0 +1,250 @@
+/* Copyright (c) 2001 Aaron Lehmann <aaronl@vitelus.com>
+
+ Permission is hereby granted, free of charge, to any person obtaining
+ a copy of this software and associated documentation files (the
+ "Software"), to deal in the Software without restriction, including
+ without limitation the rights to use, copy, modify, merge, publish,
+ distribute, sublicense, and/or sell copies of the Software, and to
+ permit persons to whom the Software is furnished to do so, subject to
+ the following conditions:
+
+ The above copyright notice and this permission notice shall be
+ included in all copies or substantial portions of the Software.
+
+ THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+ EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+ MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
+ IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY
+ CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,
+ TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
+ SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+*/
+
+/* This is my infix parser/evaluator. It is optimized for size, intended
+ * as a replacement for yacc-based parsers. However, it may well be faster
+ * than a comparable parser writen in yacc. The supported operators are
+ * listed in #defines below. Parens, order of operations, and error handling
+ * are supported. This code is threadsafe. */
+
+/* To use the routine, call it with an expression string. It returns an
+ * integer result. You will also need to define an "error" function
+ * that takes printf arguments and _does not return_, or modify the code
+ * to use another error mechanism. */
+
+#include <stdlib.h>
+#include <string.h>
+#include "libbb.h"
+
+typedef char operator;
+
+#define tok_decl(prec,id) (((id)<<5)|(prec))
+#define PREC(op) ((op)&0x1F)
+
+#define TOK_LPAREN tok_decl(0,0)
+
+#define TOK_OR tok_decl(1,0)
+
+#define TOK_AND tok_decl(2,0)
+
+#define TOK_BOR tok_decl(3,0)
+
+#define TOK_BXOR tok_decl(4,0)
+
+#define TOK_BAND tok_decl(5,0)
+
+#define TOK_EQ tok_decl(6,0)
+#define TOK_NE tok_decl(6,1)
+
+#define TOK_LT tok_decl(7,0)
+#define TOK_GT tok_decl(7,1)
+#define TOK_GE tok_decl(7,2)
+#define TOK_LE tok_decl(7,3)
+
+#define TOK_LSHIFT tok_decl(8,0)
+#define TOK_RSHIFT tok_decl(8,1)
+
+#define TOK_ADD tok_decl(9,0)
+#define TOK_SUB tok_decl(9,1)
+
+#define TOK_MUL tok_decl(10,0)
+#define TOK_DIV tok_decl(10,1)
+#define TOK_REM tok_decl(10,2)
+
+#define UNARYPREC 14
+#define TOK_BNOT tok_decl(UNARYPREC,0)
+#define TOK_NOT tok_decl(UNARYPREC,1)
+#define TOK_UMINUS tok_decl(UNARYPREC,2)
+
+#define TOK_NUM tok_decl(15,0)
+
+#define ARITH_APPLY(op) arith_apply(op, numstack, &numstackptr)
+#define NUMPTR (*numstackptr)
+static short arith_apply(operator op, long *numstack, long **numstackptr)
+{
+ if (NUMPTR == numstack) goto err;
+ if (op == TOK_UMINUS)
+ NUMPTR[-1] *= -1;
+ else if (op == TOK_NOT)
+ NUMPTR[-1] = !(NUMPTR[-1]);
+ else if (op == TOK_BNOT)
+ NUMPTR[-1] = ~(NUMPTR[-1]);
+
+ /* Binary operators */
+ else {
+ if (NUMPTR-1 == numstack) goto err;
+ --NUMPTR;
+ if (op == TOK_BOR)
+ NUMPTR[-1] |= *NUMPTR;
+ else if (op == TOK_OR)
+ NUMPTR[-1] = *NUMPTR || NUMPTR[-1];
+ else if (op == TOK_BAND)
+ NUMPTR[-1] &= *NUMPTR;
+ else if (op == TOK_AND)
+ NUMPTR[-1] = NUMPTR[-1] && *NUMPTR;
+ else if (op == TOK_EQ)
+ NUMPTR[-1] = (NUMPTR[-1] == *NUMPTR);
+ else if (op == TOK_NE)
+ NUMPTR[-1] = (NUMPTR[-1] != *NUMPTR);
+ else if (op == TOK_GE)
+ NUMPTR[-1] = (NUMPTR[-1] >= *NUMPTR);
+ else if (op == TOK_RSHIFT)
+ NUMPTR[-1] >>= *NUMPTR;
+ else if (op == TOK_LSHIFT)
+ NUMPTR[-1] <<= *NUMPTR;
+ else if (op == TOK_GT)
+ NUMPTR[-1] = (NUMPTR[-1] > *NUMPTR);
+ else if (op == TOK_LT)
+ NUMPTR[-1] = (NUMPTR[-1] < *NUMPTR);
+ else if (op == TOK_LE)
+ NUMPTR[-1] = (NUMPTR[-1] <= *NUMPTR);
+ else if (op == TOK_MUL)
+ NUMPTR[-1] *= *NUMPTR;
+ else if (op == TOK_DIV)
+ NUMPTR[-1] /= *NUMPTR;
+ else if (op == TOK_REM)
+ NUMPTR[-1] %= *NUMPTR;
+ else if (op == TOK_ADD)
+ NUMPTR[-1] += *NUMPTR;
+ else if (op == TOK_SUB)
+ NUMPTR[-1] -= *NUMPTR;
+ }
+ return 0;
+err: return(1);
+}
+
+extern long arith (const char *startbuf)
+{
+ register char arithval;
+ const char *expr = startbuf;
+
+ operator lasttok = TOK_MUL, op;
+ size_t datasizes = strlen(startbuf);
+ unsigned char prec;
+
+ long *numstack, *numstackptr;
+
+ operator *stack = alloca(datasizes * sizeof(operator)), *stackptr = stack;
+ numstack = alloca((datasizes/2+1)*sizeof(long)), numstackptr = numstack;
+
+ while ((arithval = *expr)) {
+ if (arithval == ' ' || arithval == '\n' || arithval == '\t')
+ goto prologue;
+ if ((unsigned)arithval-'0' <= 9) /* isdigit */ {
+ *numstackptr++ = strtol(expr, (char **) &expr, 10);
+ lasttok = TOK_NUM;
+ continue;
+ } if (arithval == '(') {
+ *stackptr++ = TOK_LPAREN;
+ lasttok = TOK_LPAREN;
+ goto prologue;
+ } if (arithval == ')') {
+ lasttok = TOK_NUM;
+ while (stackptr != stack) {
+ op = *--stackptr;
+ if (op == TOK_LPAREN)
+ goto prologue;
+ if(ARITH_APPLY(op)) goto err;
+ }
+ goto err; /* Mismatched parens */
+ } if (arithval == '|') {
+ if (*++expr == '|')
+ op = TOK_OR;
+ else {
+ --expr;
+ op = TOK_BOR;
+ }
+ } else if (arithval == '&') {
+ if (*++expr == '&')
+ op = TOK_AND;
+ else {
+ --expr;
+ op = TOK_BAND;
+ }
+ } else if (arithval == '=') {
+ if (*++expr != '=') goto err; /* Unknown token */
+ op = TOK_EQ;
+ } else if (arithval == '!') {
+ if (*++expr == '=')
+ op = TOK_NE;
+ else {
+ --expr;
+ op = TOK_NOT;
+ }
+ } else if (arithval == '>') {
+ switch (*++expr) {
+ case '=':
+ op = TOK_GE;
+ break;
+ case '>':
+ op = TOK_RSHIFT;
+ break;
+ default:
+ --expr;
+ op = TOK_GT;
+ }
+ } else if (arithval == '<') {
+ switch (*++expr) {
+ case '=':
+ op = TOK_LE;
+ break;
+ case '<':
+ op = TOK_LSHIFT;
+ break;
+ default:
+ --expr;
+ op = TOK_LT;
+ }
+ } else if (arithval == '*')
+ op = TOK_MUL;
+ else if (arithval == '/')
+ op = TOK_DIV;
+ else if (arithval == '%')
+ op = TOK_REM;
+ else if (arithval == '+') {
+ if (lasttok != TOK_NUM) goto prologue; /* Unary plus */
+ op = TOK_ADD;
+ } else if (arithval == '-')
+ op = (lasttok == TOK_NUM) ? TOK_SUB : TOK_UMINUS;
+ else if (arithval == '~')
+ op = TOK_BNOT;
+ else goto err; /* Unknown token */
+
+ prec = PREC(op);
+ if (prec != UNARYPREC)
+ while (stackptr != stack && PREC(stackptr[-1]) >= prec)
+ if(ARITH_APPLY(*--stackptr)) goto err;
+ *stackptr++ = op;
+ lasttok = op;
+prologue: ++expr;
+ } /* yay */
+
+ while (stackptr != stack)
+ if(ARITH_APPLY(*--stackptr)) goto err;
+ if (numstackptr != numstack+1) {
+err:
+ return -1;
+ /* NOTREACHED */
+ }
+
+ return *numstack;
+}
diff --git a/libbb/libbb.h b/libbb/libbb.h
index 3cf932d..66acc22 100644
--- a/libbb/libbb.h
+++ b/libbb/libbb.h
@@ -212,6 +212,8 @@
char *concat_path_file(const char *path, const char *filename);
char *last_char_is(const char *s, int c);
+extern long arith (const char *startbuf);
+
typedef struct file_headers_s {
char *name;
char *link_name;
diff --git a/shell/ash.c b/shell/ash.c
index bb5bf36..9a5435e 100644
--- a/shell/ash.c
+++ b/shell/ash.c
@@ -51,9 +51,8 @@
#define ASH_ALIAS
/* If you need ash to act as a full Posix shell, with full math
- * support, enable this. This option needs some work, since it
- * doesn't compile right now... */
-#undef ASH_MATH_SUPPORT
+ * support, enable this. This adds a bit over 2k an x86 system. */
+#define ASH_MATH_SUPPORT
/* Getopts is used by shell procedures to parse positional parameters.
* You probably want to leave this disabled, and use the busybox getopt
@@ -80,6 +79,7 @@
#undef FNMATCH_BROKEN
#undef GLOB_BROKEN
#undef _GNU_SOURCE
+#undef __USE_GNU
#include <assert.h>
#include <ctype.h>
@@ -1562,8 +1562,10 @@
#endif
#ifdef ASH_MATH_SUPPORT
-/* The generated file arith.c has been snipped. If you want this
- * stuff back in, feel free to add it to your own copy. */
+/* The generated file arith.c has been replaced with a custom hand
+ * written implementation written by Aaron Lehmann <aaronl@vitelus.com>.
+ * This is now part of libbb, so that it can be used by all the shells
+ * in busybox. */
#define ARITH_NUM 257
#define ARITH_LPAREN 258
#define ARITH_RPAREN 259
@@ -1592,11 +1594,8 @@
static void expari (int);
/* From arith.y */
-static int arith (const char *);
+static long ash_arith(const char *p);
static int expcmd (int , char **);
-static void arith_lex_reset (void);
-static int yylex (void);
-
#endif
static char *trap[NSIG]; /* trap handler commands */
@@ -2173,52 +2172,22 @@
}
-#ifdef __STDC__
-static void
+static void
error(const char *msg, ...)
-#else
-static void
-error(va_alist)
- va_dcl
-#endif
{
-#ifndef __STDC__
- const char *msg;
-#endif
va_list ap;
-#ifdef __STDC__
va_start(ap, msg);
-#else
- va_start(ap);
- msg = va_arg(ap, const char *);
-#endif
exverror(EXERROR, msg, ap);
/* NOTREACHED */
va_end(ap);
}
-#ifdef __STDC__
static void
exerror(int cond, const char *msg, ...)
-#else
-static void
-exerror(va_alist)
- va_dcl
-#endif
{
-#ifndef __STDC__
- int cond;
- const char *msg;
-#endif
va_list ap;
-#ifdef __STDC__
va_start(ap, msg);
-#else
- va_start(ap);
- cond = va_arg(ap, int);
- msg = va_arg(ap, const char *);
-#endif
exverror(cond, msg, ap);
/* NOTREACHED */
va_end(ap);
@@ -4914,7 +4883,7 @@
removerecordregions(begoff);
if (quotes)
rmescapes(p+2);
- result = arith(p+2);
+ result = ash_arith(p+2);
snprintf(p, 12, "%d", result);
while (*p++)
@@ -11952,13 +11921,7 @@
trace(const char *fmt, ...)
{
va_list va;
-#ifdef __STDC__
va_start(va, fmt);
-#else
- char *fmt;
- va_start(va);
- fmt = va_arg(va, char *);
-#endif
if (tracefile != NULL) {
(void) vfprintf(tracefile, fmt, va);
if (strchr(fmt, '\n'))
@@ -12657,7 +12620,6 @@
return 0;
}
-
/*
* The "local" command.
*/
@@ -12916,7 +12878,7 @@
/*
* Copyright (c) 1999 Herbert Xu <herbert@debian.org>
* This file contains code for the times builtin.
- * $Id: ash.c,v 1.13 2001/07/26 05:58:40 russ Exp $
+ * $Id: ash.c,v 1.14 2001/07/30 21:41:37 andersen Exp $
*/
static int timescmd (int argc, char **argv)
{
@@ -12937,6 +12899,51 @@
}
+#ifdef ASH_MATH_SUPPORT
+/* The exp(1) builtin. */
+int expcmd(int argc, char **argv)
+{
+ const char *p;
+ char *concat;
+ char **ap;
+ long i;
+
+ if (argc > 1) {
+ p = argv[1];
+ if (argc > 2) {
+ /* concatenate arguments */
+ STARTSTACKSTR(concat);
+ ap = argv + 2;
+ for (;;) {
+ while (*p)
+ STPUTC(*p++, concat);
+ if ((p = *ap++) == NULL)
+ break;
+ STPUTC(' ', concat);
+ }
+ STPUTC('\0', concat);
+ p = grabstackstr(concat);
+ }
+ } else
+ p = "";
+
+ i = ash_arith(p);
+
+ printf("%ld\n", i);
+ return (! i);
+}
+
+static long ash_arith(const char *p)
+{
+ long i = arith(p);
+ if (i <0)
+ error("arith: syntax error: \"%s\"\n", p);
+ return i;
+}
+#endif
+
+
+
/*-
* Copyright (c) 1989, 1991, 1993, 1994
* The Regents of the University of California. All rights reserved.