/*- * 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. * * @(#)memalloc.c 8.3 (Berkeley) 5/4/95 * $FreeBSD: src/bin/sh/memalloc.c,v 1.27 2005/10/28 10:45:19 stefanf Exp $ * $DragonFly: src/bin/sh/memalloc.c,v 1.5 2007/01/14 03:59:57 pavalos Exp $ */ #include #include "shell.h" #include "output.h" #include "memalloc.h" #include "error.h" #include "mystring.h" #include "expand.h" #include #include /* * Like malloc, but returns an error when out of space. */ pointer ckmalloc(int nbytes) { pointer p; INTOFF; p = malloc(nbytes); INTON; if (p == NULL) error("Out of space"); return p; } /* * Same for realloc. */ pointer ckrealloc(pointer p, int nbytes) { INTOFF; p = realloc(p, nbytes); INTON; if (p == NULL) error("Out of space"); return p; } void ckfree(pointer p) { INTOFF; free(p); INTON; } /* * Make a copy of a string in safe storage. */ char * savestr(const 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 496 was chosen because with 16-byte alignment the total size * for the allocated block is 512. */ #define MINSIZE 496 /* minimum size of a block. */ struct stack_block { struct stack_block *prev; /* Data follows */ }; #define SPACE(sp) ((char*)(sp) + ALIGN(sizeof(struct stack_block))) STATIC struct stack_block *stackp; STATIC struct stackmark *markp; char *stacknxt; int stacknleft; int sstrnleft; int herefd = -1; static void stnewblock(int nbytes) { struct stack_block *sp; int allocsize; if (nbytes < MINSIZE) nbytes = MINSIZE; allocsize = ALIGN(sizeof(struct stack_block)) + ALIGN(nbytes); INTOFF; sp = ckmalloc(allocsize); sp->prev = stackp; stacknxt = SPACE(sp); stacknleft = allocsize - (stacknxt - (char*)sp); stackp = sp; INTON; } pointer stalloc(int nbytes) { char *p; nbytes = ALIGN(nbytes); if (nbytes > stacknleft) stnewblock(nbytes); p = stacknxt; stacknxt += nbytes; stacknleft -= nbytes; return p; } void stunalloc(pointer p) { if (p == NULL) { /*DEBUG */ write(STDERR_FILENO, "stunalloc\n", 10); abort(); } stacknleft += stacknxt - (char *)p; stacknxt = p; } void setstackmark(struct stackmark *mark) { mark->stackp = stackp; mark->stacknxt = stacknxt; mark->stacknleft = stacknleft; mark->marknext = markp; markp = mark; } void popstackmark(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(void) { char *p; int newlen; char *oldspace; int oldlen; struct stack_block *sp; struct stack_block *oldstackp; struct stackmark *xmark; newlen = (stacknleft == 0) ? MINSIZE : stacknleft * 2 + 100; newlen = ALIGN(newlen); oldspace = stacknxt; oldlen = stacknleft; if (stackp != NULL && stacknxt == SPACE(stackp)) { INTOFF; oldstackp = stackp; stackp = oldstackp->prev; sp = ckrealloc((pointer)oldstackp, newlen); sp->prev = stackp; stackp = sp; stacknxt = SPACE(sp); stacknleft = newlen - (stacknxt - (char*)sp); /* * Stack marks pointing to the start of the old block * must be relocated to point to the new block */ 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); if (oldlen != 0) memcpy(p, oldspace, oldlen); stunalloc(p); } } void grabstackblock(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(void) { int len; 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(void) { int len; len = stackblocksize() - sstrnleft; growstackblock(); sstrnleft = stackblocksize() - len; return stackblock() + len; } void ungrabstackstr(char *s, char *p) { stacknleft += stacknxt - s; stacknxt = s; sstrnleft = stacknleft - (p - s); }