/* $NetBSD: memalloc.c,v 1.28 2003/08/07 09:05:34 agc 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. 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. */ #if 0 #ifndef lint static char sccsid[] = "@(#)memalloc.c 8.3 (Berkeley) 5/4/95"; #else __RCSID("$NetBSD: memalloc.c,v 1.28 2003/08/07 09:05:34 agc Exp $"); #endif /* not lint */ #endif #include #include "shell.h" #include "output.h" #include "memalloc.h" #include "error.h" #include "machdep.h" #include "mystring.h" #include "shinstance.h" /* * Like malloc, but returns an error when out of space. */ pointer ckmalloc(size_t nbytes) { pointer p; p = malloc(nbytes); if (p == NULL) error(NULL, "Out of space"); return p; } /* * Same for realloc. */ pointer ckrealloc(pointer p, size_t nbytes) { p = realloc(p, nbytes); if (p == NULL) error(NULL, "Out of space"); return p; } /* * 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 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(shinstance *psh, size_t nbytes) { char *p; nbytes = SHELL_ALIGN(nbytes); if (nbytes > psh->stacknleft) { size_t blocksize; struct stack_block *sp; blocksize = nbytes; if (blocksize < MINSIZE) blocksize = MINSIZE; INTOFF; sp = ckmalloc(sizeof(struct stack_block) - MINSIZE + blocksize); sp->prev = psh->stackp; psh->stacknxt = sp->space; psh->stacknleft = (int)blocksize; psh->stackp = sp; INTON; } p = psh->stacknxt; psh->stacknxt += nbytes; psh->stacknleft -= (int)nbytes; return p; } void stunalloc(shinstance *psh, pointer p) { if (p == NULL) { /*DEBUG */ shfile_write(&psh->fdtab, 2, "stunalloc\n", 10); sh_abort(psh); } psh->stacknleft += (int)(psh->stacknxt - (char *)p); psh->stacknxt = p; } void setstackmark(shinstance *psh, struct stackmark *mark) { mark->stackp = psh->stackp; mark->stacknxt = psh->stacknxt; mark->stacknleft = psh->stacknleft; mark->marknext = psh->markp; psh->markp = mark; } void popstackmark(shinstance *psh, struct stackmark *mark) { struct stack_block *sp; INTOFF; psh->markp = mark->marknext; while (psh->stackp != mark->stackp) { sp = psh->stackp; psh->stackp = sp->prev; ckfree(sp); } psh->stacknxt = mark->stacknxt; psh->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(shinstance *psh) { int newlen = SHELL_ALIGN(psh->stacknleft * 2 + 100); if (psh->stacknxt == psh->stackp->space && psh->stackp != &psh->stackbase) { struct stack_block *oldstackp; struct stackmark *xmark; struct stack_block *sp; INTOFF; oldstackp = psh->stackp; sp = psh->stackp; psh->stackp = sp->prev; sp = ckrealloc((pointer)sp, sizeof(struct stack_block) - MINSIZE + newlen); sp->prev = psh->stackp; psh->stackp = sp; psh->stacknxt = sp->space; psh->stacknleft = newlen; /* * Stack marks pointing to the start of the old block * must be relocated to point to the new block */ xmark = psh->markp; while (xmark != NULL && xmark->stackp == oldstackp) { xmark->stackp = psh->stackp; xmark->stacknxt = psh->stacknxt; xmark->stacknleft = psh->stacknleft; xmark = xmark->marknext; } INTON; } else { char *oldspace = psh->stacknxt; int oldlen = psh->stacknleft; char *p = stalloc(psh, newlen); (void)memcpy(p, oldspace, oldlen); psh->stacknxt = p; /* free the space */ psh->stacknleft += newlen; /* we just allocated */ } } void grabstackblock(shinstance *psh, int len) { len = SHELL_ALIGN(len); psh->stacknxt += len; psh->stacknleft -= len; } /* * The following routines are somewhat easier to use than 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(psh, 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(psh). 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(shinstance *psh) { int len = stackblocksize(psh); if (psh->herefd >= 0 && len >= 1024) { xwrite(psh, psh->herefd, stackblock(psh), len); psh->sstrnleft = len - 1; return stackblock(psh); } growstackblock(psh); psh->sstrnleft = stackblocksize(psh) - len - 1; return stackblock(psh) + len; } /* * Called from CHECKSTRSPACE. */ char * makestrspace(shinstance *psh) { int len = stackblocksize(psh) - psh->sstrnleft; growstackblock(psh); psh->sstrnleft = stackblocksize(psh) - len; return stackblock(psh) + len; } void ungrabstackstr(shinstance *psh, char *s, char *p) { psh->stacknleft += (int)(psh->stacknxt - s); psh->stacknxt = s; psh->sstrnleft = (int)(psh->stacknleft - (p - s)); }