X-Git-Url: http://erislabs.net/gitweb/?a=blobdiff_plain;f=lib%2Falloca.c;h=3a1f4e273a56b8f4f65e39c35577a1826343de24;hb=b4548f0e8f674d7c914b622c5ace7e2686ab0f87;hp=f4d6ebf134cdcf0aa5291d97c1bce0eb10c624bc;hpb=2dbc26c088da1858ee8f038194fb9bab4faec440;p=gnulib.git diff --git a/lib/alloca.c b/lib/alloca.c index f4d6ebf13..3a1f4e273 100644 --- a/lib/alloca.c +++ b/lib/alloca.c @@ -21,12 +21,22 @@ allocating any. It is a good idea to use alloca(0) in your main control loop, etc. to force garbage collection. */ -#ifdef HAVE_CONFIG_H #include -#endif + +#include + +#include +#include #ifdef emacs -#include "blockinput.h" +# include "lisp.h" +# include "blockinput.h" +# ifdef EMACS_FREE +# undef free +# define free EMACS_FREE +# endif +#else +# define memory_full() abort () #endif /* If compiling with GCC 2, this file's not needed. */ @@ -34,54 +44,33 @@ /* If someone has defined alloca as a macro, there must be some other way alloca is supposed to work. */ -#ifndef alloca +# ifndef alloca -#ifdef emacs -#ifdef static +# ifdef emacs +# ifdef static /* actually, only want this if static is defined as "" -- this is for usg, in which emacs must undefine static in order to make unexec workable */ -#ifndef STACK_DIRECTION +# ifndef STACK_DIRECTION you lose -- must know STACK_DIRECTION at compile-time -#endif /* STACK_DIRECTION undefined */ -#endif /* static */ -#endif /* emacs */ +/* Using #error here is not wise since this file should work for + old and obscure compilers. */ +# endif /* STACK_DIRECTION undefined */ +# endif /* static */ +# endif /* emacs */ /* If your stack is a linked list of frames, you have to provide an "address metric" ADDRESS_FUNCTION macro. */ -#if defined (CRAY) && defined (CRAY_STACKSEG_END) +# if defined (CRAY) && defined (CRAY_STACKSEG_END) long i00afunc (); -#define ADDRESS_FUNCTION(arg) (char *) i00afunc (&(arg)) -#else -#define ADDRESS_FUNCTION(arg) &(arg) -#endif - -#if __STDC__ -typedef void *pointer; -#else -typedef char *pointer; -#endif - -#define NULL 0 - -/* Different portions of Emacs need to call different versions of - malloc. The Emacs executable needs alloca to call xmalloc, because - ordinary malloc isn't protected from input signals. On the other - hand, the utilities in lib-src need alloca to call malloc; some of - them are very simple, and don't have an xmalloc routine. - - Non-Emacs programs expect this to call xmalloc. - - Callers below should use malloc. */ - -#ifndef emacs -#define malloc xmalloc -#endif -extern pointer malloc (); +# define ADDRESS_FUNCTION(arg) (char *) i00afunc (&(arg)) +# else +# define ADDRESS_FUNCTION(arg) &(arg) +# endif /* Define STACK_DIRECTION if you know the direction of stack growth for your system; otherwise it will be automatically @@ -91,21 +80,21 @@ extern pointer malloc (); STACK_DIRECTION < 0 => grows toward lower addresses STACK_DIRECTION = 0 => direction of growth unknown */ -#ifndef STACK_DIRECTION -#define STACK_DIRECTION 0 /* Direction unknown. */ -#endif +# ifndef STACK_DIRECTION +# define STACK_DIRECTION 0 /* Direction unknown. */ +# endif -#if STACK_DIRECTION != 0 +# if STACK_DIRECTION != 0 -#define STACK_DIR STACK_DIRECTION /* Known at compile-time. */ +# define STACK_DIR STACK_DIRECTION /* Known at compile-time. */ -#else /* STACK_DIRECTION == 0; need run-time code. */ +# else /* STACK_DIRECTION == 0; need run-time code. */ static int stack_dir; /* 1 or -1 once known. */ -#define STACK_DIR stack_dir +# define STACK_DIR stack_dir static void -find_stack_direction () +find_stack_direction (void) { static char *addr = NULL; /* Address of first `dummy', once known. */ auto char dummy; /* To get stack address. */ @@ -126,7 +115,7 @@ find_stack_direction () } } -#endif /* STACK_DIRECTION == 0 */ +# endif /* STACK_DIRECTION == 0 */ /* An "alloca header" is used to: (a) chain together all alloca'ed blocks; @@ -135,9 +124,9 @@ find_stack_direction () It is very important that sizeof(header) agree with malloc alignment chunk size. The following default should work okay. */ -#ifndef ALIGN_SIZE -#define ALIGN_SIZE sizeof(double) -#endif +# ifndef ALIGN_SIZE +# define ALIGN_SIZE sizeof(double) +# endif typedef union hdr { @@ -158,17 +147,16 @@ static header *last_alloca_header = NULL; /* -> last alloca header. */ caller, but that method cannot be made to work for some implementations of C, for example under Gould's UTX/32. */ -pointer -alloca (size) - unsigned size; +void * +alloca (size_t size) { auto char probe; /* Probes stack depth: */ register char *depth = ADDRESS_FUNCTION (probe); -#if STACK_DIRECTION == 0 +# if STACK_DIRECTION == 0 if (STACK_DIR == 0) /* Unknown growth direction. */ find_stack_direction (); -#endif +# endif /* Reclaim garbage, defined as all alloca'd storage that was allocated from deeper in the stack than currently. */ @@ -176,9 +164,9 @@ alloca (size) { register header *hp; /* Traverses linked list. */ -#ifdef emacs +# ifdef emacs BLOCK_INPUT; -#endif +# endif for (hp = last_alloca_header; hp != NULL;) if ((STACK_DIR > 0 && hp->h.deep > depth) @@ -186,7 +174,7 @@ alloca (size) { register header *np = hp->h.next; - free ((pointer) hp); /* Collect garbage. */ + free (hp); /* Collect garbage. */ hp = np; /* -> next header. */ } @@ -195,9 +183,9 @@ alloca (size) last_alloca_header = hp; /* -> last valid storage. */ -#ifdef emacs +# ifdef emacs UNBLOCK_INPUT; -#endif +# endif } if (size == 0) @@ -206,29 +194,38 @@ alloca (size) /* Allocate combined header + user data storage. */ { - register pointer new = malloc (sizeof (header) + size); /* Address of header. */ + register header *new; + + size_t combined_size = sizeof (header) + size; + if (combined_size < sizeof (header)) + memory_full (); + + new = malloc (combined_size); + + if (! new) + memory_full (); - ((header *) new)->h.next = last_alloca_header; - ((header *) new)->h.deep = depth; + new->h.next = last_alloca_header; + new->h.deep = depth; - last_alloca_header = (header *) new; + last_alloca_header = new; /* User storage begins just after header. */ - return (pointer) ((char *) new + sizeof (header)); + return (void *) (new + 1); } } -#if defined (CRAY) && defined (CRAY_STACKSEG_END) +# if defined (CRAY) && defined (CRAY_STACKSEG_END) -#ifdef DEBUG_I00AFUNC -#include -#endif +# ifdef DEBUG_I00AFUNC +# include +# endif -#ifndef CRAY_STACK -#define CRAY_STACK -#ifndef CRAY2 +# ifndef CRAY_STACK +# define CRAY_STACK +# ifndef CRAY2 /* Stack structures for CRAY-1, CRAY X-MP, and CRAY Y-MP */ struct stack_control_header { @@ -280,7 +277,7 @@ struct stack_segment_linkage long sss7; }; -#else /* CRAY2 */ +# else /* CRAY2 */ /* The following structure defines the vector of words returned by the STKSTAT library routine. */ struct stk_stat @@ -333,10 +330,10 @@ struct stk_trailer long unknown14; }; -#endif /* CRAY2 */ -#endif /* not CRAY_STACK */ +# endif /* CRAY2 */ +# endif /* not CRAY_STACK */ -#ifdef CRAY2 +# ifdef CRAY2 /* Determine a "stack measure" for an arbitrary ADDRESS. I doubt that "lint" will like this much. */ @@ -407,7 +404,7 @@ i00afunc (long *address) return (result); } -#else /* not CRAY2 */ +# else /* not CRAY2 */ /* Stack address function for a CRAY-1, CRAY X-MP, or CRAY Y-MP. Determine the number of the cell within the stack, given the address of the cell. The purpose of this @@ -452,9 +449,9 @@ i00afunc (long address) while (!(this_segment <= address && address <= stkl)) { -#ifdef DEBUG_I00AFUNC +# ifdef DEBUG_I00AFUNC fprintf (stderr, "%011o %011o %011o\n", this_segment, address, stkl); -#endif +# endif if (pseg == 0) break; stkl = stkl - pseg; @@ -473,9 +470,9 @@ i00afunc (long address) while (pseg != 0) { -#ifdef DEBUG_I00AFUNC +# ifdef DEBUG_I00AFUNC fprintf (stderr, "%011o %011o\n", pseg, size); -#endif +# endif stkl = stkl - pseg; ssptr = (struct stack_segment_linkage *) stkl; size = ssptr->sssize; @@ -485,8 +482,8 @@ i00afunc (long address) return (result); } -#endif /* not CRAY2 */ -#endif /* CRAY */ +# endif /* not CRAY2 */ +# endif /* CRAY */ -#endif /* no alloca */ +# endif /* no alloca */ #endif /* not GCC version 2 */