| 0,0 → 1,329 |
|---|
| /* $NetBSD: memalloc.c,v 1.23 2000/11/01 19:56:01 christos Exp $ */ |
| |
| /*- |
| * Copyright (c) 1991, 1993 |
| * 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. |
| */ |
| |
| #include <sys/cdefs.h> |
| #ifndef lint |
| #if 0 |
| static char sccsid[] = "@(#)memalloc.c 8.3 (Berkeley) 5/4/95"; |
| #else |
| __RCSID("$NetBSD: memalloc.c,v 1.23 2000/11/01 19:56:01 christos Exp $"); |
| #endif |
| #endif /* not lint */ |
| |
| #include <stdlib.h> |
| #include <unistd.h> |
| |
| #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) |
| int nbytes; |
| { |
| pointer p; |
| |
| INTOFF; |
| p = malloc(nbytes); |
| INTON; |
| if (p == NULL) |
| error("Out of space"); |
| return p; |
| } |
| |
| |
| /* |
| * Same for realloc. |
| */ |
| |
| pointer |
| ckrealloc(p, nbytes) |
| pointer p; |
| int nbytes; |
| { |
| |
| 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; |
| { |
| 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; |
| struct stackmark *markp; |
| char *stacknxt = stackbase.space; |
| int stacknleft = MINSIZE; |
| int sstrnleft; |
| int herefd = -1; |
| |
| |
| |
| pointer |
| stalloc(nbytes) |
| int nbytes; |
| { |
| 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; |
| mark->marknext = markp; |
| markp = mark; |
| } |
| |
| |
| void |
| popstackmark(mark) |
| struct stackmark *mark; |
| { |
| struct stack_block *sp; |
| |
| INTOFF; |
| markp = mark->marknext; |
| 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 = ALIGN(stacknleft * 2 + 100); |
| char *oldspace = stacknxt; |
| int oldlen = stacknleft; |
| struct stack_block *sp; |
| struct stack_block *oldstackp; |
| |
| if (stacknxt == stackp->space && stackp != &stackbase) { |
| INTOFF; |
| oldstackp = stackp; |
| 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; |
| { |
| /* Stack marks pointing to the start of the old block |
| * must be relocated to point to the new block |
| */ |
| struct stackmark *xmark; |
| xmark = markp; |
| while (xmark != NULL && xmark->stackp == oldstackp) { |
| xmark->stackp = stackp; |
| xmark->stacknxt = stacknxt; |
| xmark->stacknleft = stacknleft; |
| xmark = xmark->marknext; |
| } |
| } |
| INTON; |
| } else { |
| p = stalloc(newlen); |
| memcpy(p, oldspace, oldlen); |
| stacknxt = p; /* free the space */ |
| stacknleft += newlen; /* we just allocated */ |
| } |
| } |
| |
| |
| |
| void |
| grabstackblock(len) |
| int 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); |
| } |