293 lines
6.9 KiB
C
Executable File
293 lines
6.9 KiB
C
Executable File
/*-
|
|
* Copyright (c) 1991 The Regents of the University of California.
|
|
* All rights reserved.
|
|
*
|
|
* This code is derived from software contributed to Berkeley by
|
|
* Kenneth Almquist.
|
|
*
|
|
* Redistribution and use in source and binary forms, with or without
|
|
* modification, are permitted provided that the following conditions
|
|
* are met:
|
|
* 1. Redistributions of source code must retain the above copyright
|
|
* notice, this list of conditions and the following disclaimer.
|
|
* 2. Redistributions in binary form must reproduce the above copyright
|
|
* notice, this list of conditions and the following disclaimer in the
|
|
* documentation and/or other materials provided with the distribution.
|
|
* 3. All advertising materials mentioning features or use of this software
|
|
* must display the following acknowledgement:
|
|
* This product includes software developed by the University of
|
|
* California, Berkeley and its contributors.
|
|
* 4. Neither the name of the University nor the names of its contributors
|
|
* may be used to endorse or promote products derived from this software
|
|
* without specific prior written permission.
|
|
*
|
|
* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
|
|
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
|
|
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
|
|
* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
|
|
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
|
|
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
|
|
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
|
|
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
|
|
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
|
|
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
|
|
* SUCH DAMAGE.
|
|
*/
|
|
|
|
#ifndef lint
|
|
static char sccsid[] = "@(#)memalloc.c 5.2 (Berkeley) 3/13/91";
|
|
#endif /* not lint */
|
|
|
|
#include "shell.h"
|
|
#include "output.h"
|
|
#include "memalloc.h"
|
|
#include "error.h"
|
|
#include "machdep.h"
|
|
#include "mystring.h"
|
|
|
|
/*
|
|
* Like malloc, but returns an error when out of space.
|
|
*/
|
|
|
|
pointer
|
|
ckmalloc(nbytes) {
|
|
register pointer p;
|
|
pointer malloc();
|
|
|
|
if ((p = malloc(nbytes)) == NULL)
|
|
error("Out of space");
|
|
return p;
|
|
}
|
|
|
|
|
|
/*
|
|
* Same for realloc.
|
|
*/
|
|
|
|
pointer
|
|
ckrealloc(p, nbytes)
|
|
register pointer p;
|
|
{
|
|
pointer realloc();
|
|
|
|
if ((p = realloc(p, nbytes)) == NULL)
|
|
error("Out of space");
|
|
return p;
|
|
}
|
|
|
|
|
|
/*
|
|
* Make a copy of a string in safe storage.
|
|
*/
|
|
|
|
char *
|
|
savestr(s)
|
|
char *s;
|
|
{
|
|
register char *p;
|
|
|
|
p = ckmalloc(strlen(s) + 1);
|
|
scopy(s, p);
|
|
return p;
|
|
}
|
|
|
|
|
|
/*
|
|
* Parse trees for commands are allocated in lifo order, so we use a stack
|
|
* to make this more efficient, and also to avoid all sorts of exception
|
|
* handling code to handle interrupts in the middle of a parse.
|
|
*
|
|
* The size 504 was chosen because the Ultrix malloc handles that size
|
|
* well.
|
|
*/
|
|
|
|
#define MINSIZE 504 /* minimum size of a block */
|
|
|
|
|
|
struct stack_block {
|
|
struct stack_block *prev;
|
|
char space[MINSIZE];
|
|
};
|
|
|
|
struct stack_block stackbase;
|
|
struct stack_block *stackp = &stackbase;
|
|
char *stacknxt = stackbase.space;
|
|
int stacknleft = MINSIZE;
|
|
int sstrnleft;
|
|
int herefd = -1;
|
|
|
|
|
|
|
|
pointer
|
|
stalloc(nbytes) {
|
|
register char *p;
|
|
|
|
nbytes = ALIGN(nbytes);
|
|
if (nbytes > stacknleft) {
|
|
int blocksize;
|
|
struct stack_block *sp;
|
|
|
|
blocksize = nbytes;
|
|
if (blocksize < MINSIZE)
|
|
blocksize = MINSIZE;
|
|
INTOFF;
|
|
sp = ckmalloc(sizeof(struct stack_block) - MINSIZE + blocksize);
|
|
sp->prev = stackp;
|
|
stacknxt = sp->space;
|
|
stacknleft = blocksize;
|
|
stackp = sp;
|
|
INTON;
|
|
}
|
|
p = stacknxt;
|
|
stacknxt += nbytes;
|
|
stacknleft -= nbytes;
|
|
return p;
|
|
}
|
|
|
|
|
|
void
|
|
stunalloc(p)
|
|
pointer p;
|
|
{
|
|
if (p == NULL) { /*DEBUG */
|
|
write(2, "stunalloc\n", 10);
|
|
abort();
|
|
}
|
|
stacknleft += stacknxt - (char *)p;
|
|
stacknxt = p;
|
|
}
|
|
|
|
|
|
|
|
void
|
|
setstackmark(mark)
|
|
struct stackmark *mark;
|
|
{
|
|
mark->stackp = stackp;
|
|
mark->stacknxt = stacknxt;
|
|
mark->stacknleft = stacknleft;
|
|
}
|
|
|
|
|
|
void
|
|
popstackmark(mark)
|
|
struct stackmark *mark;
|
|
{
|
|
struct stack_block *sp;
|
|
|
|
INTOFF;
|
|
while (stackp != mark->stackp) {
|
|
sp = stackp;
|
|
stackp = sp->prev;
|
|
ckfree(sp);
|
|
}
|
|
stacknxt = mark->stacknxt;
|
|
stacknleft = mark->stacknleft;
|
|
INTON;
|
|
}
|
|
|
|
|
|
/*
|
|
* When the parser reads in a string, it wants to stick the string on the
|
|
* stack and only adjust the stack pointer when it knows how big the
|
|
* string is. Stackblock (defined in stack.h) returns a pointer to a block
|
|
* of space on top of the stack and stackblocklen returns the length of
|
|
* this block. Growstackblock will grow this space by at least one byte,
|
|
* possibly moving it (like realloc). Grabstackblock actually allocates the
|
|
* part of the block that has been used.
|
|
*/
|
|
|
|
void
|
|
growstackblock() {
|
|
char *p;
|
|
int newlen = stacknleft * 2 + 100;
|
|
char *oldspace = stacknxt;
|
|
int oldlen = stacknleft;
|
|
struct stack_block *sp;
|
|
|
|
if (stacknxt == stackp->space && stackp != &stackbase) {
|
|
INTOFF;
|
|
sp = stackp;
|
|
stackp = sp->prev;
|
|
sp = ckrealloc((pointer)sp, sizeof(struct stack_block) - MINSIZE + newlen);
|
|
sp->prev = stackp;
|
|
stackp = sp;
|
|
stacknxt = sp->space;
|
|
stacknleft = newlen;
|
|
INTON;
|
|
} else {
|
|
p = stalloc(newlen);
|
|
bcopy(oldspace, p, oldlen);
|
|
stacknxt = p; /* free the space */
|
|
stacknleft += newlen; /* we just allocated */
|
|
}
|
|
}
|
|
|
|
|
|
|
|
void
|
|
grabstackblock(len) {
|
|
len = ALIGN(len);
|
|
stacknxt += len;
|
|
stacknleft -= len;
|
|
}
|
|
|
|
|
|
|
|
/*
|
|
* The following routines are somewhat easier to use that the above.
|
|
* The user declares a variable of type STACKSTR, which may be declared
|
|
* to be a register. The macro STARTSTACKSTR initializes things. Then
|
|
* the user uses the macro STPUTC to add characters to the string. In
|
|
* effect, STPUTC(c, p) is the same as *p++ = c except that the stack is
|
|
* grown as necessary. When the user is done, she can just leave the
|
|
* string there and refer to it using stackblock(). Or she can allocate
|
|
* the space for it using grabstackstr(). If it is necessary to allow
|
|
* someone else to use the stack temporarily and then continue to grow
|
|
* the string, the user should use grabstack to allocate the space, and
|
|
* then call ungrabstr(p) to return to the previous mode of operation.
|
|
*
|
|
* USTPUTC is like STPUTC except that it doesn't check for overflow.
|
|
* CHECKSTACKSPACE can be called before USTPUTC to ensure that there
|
|
* is space for at least one character.
|
|
*/
|
|
|
|
|
|
char *
|
|
growstackstr() {
|
|
int len = stackblocksize();
|
|
if (herefd >= 0 && len >= 1024) {
|
|
xwrite(herefd, stackblock(), len);
|
|
sstrnleft = len - 1;
|
|
return stackblock();
|
|
}
|
|
growstackblock();
|
|
sstrnleft = stackblocksize() - len - 1;
|
|
return stackblock() + len;
|
|
}
|
|
|
|
|
|
/*
|
|
* Called from CHECKSTRSPACE.
|
|
*/
|
|
|
|
char *
|
|
makestrspace() {
|
|
int len = stackblocksize() - sstrnleft;
|
|
growstackblock();
|
|
sstrnleft = stackblocksize() - len;
|
|
return stackblock() + len;
|
|
}
|
|
|
|
|
|
|
|
void
|
|
ungrabstackstr(s, p)
|
|
char *s;
|
|
char *p;
|
|
{
|
|
stacknleft += stacknxt - s;
|
|
stacknxt = s;
|
|
sstrnleft = stacknleft - (p - s);
|
|
}
|