X-Git-Url: http://git.efficios.com/?a=blobdiff_plain;f=libiberty%2Falloca.c;h=9b2e9cb12b63b494b2de76ba74ec9a04629e8202;hb=63ffd7c9131c0e9723016d33cf8d435cc508d02b;hp=0f8a21511db8f5112a4042762f6f8f0c4d5e5658;hpb=dc9e099fc0eced486ae2b49455c9da113c11f4ff;p=deliverable%2Fbinutils-gdb.git diff --git a/libiberty/alloca.c b/libiberty/alloca.c index 0f8a21511d..9b2e9cb12b 100644 --- a/libiberty/alloca.c +++ b/libiberty/alloca.c @@ -21,10 +21,33 @@ allocating any. It is a good idea to use alloca(0) in your main control loop, etc. to force garbage collection. */ +/* + +@deftypefn Replacement void* alloca (size_t @var{size}) + +This function allocates memory which will be automatically reclaimed +after the procedure exits. The @libib{} implementation does not free +the memory immediately but will do so eventually during subsequent +calls to this function. Memory is allocated using @code{xmalloc} under +normal circumstances. + +The header file @file{alloca-conf.h} can be used in conjunction with the +GNU Autoconf test @code{AC_FUNC_ALLOCA} to test for and properly make +available this function. The @code{AC_FUNC_ALLOCA} test requires that +client code use a block of preprocessor code to be safe (see the Autoconf +manual for more); this header incorporates that logic and more, including +the possibility of a GCC built-in function. + +@end deftypefn + +*/ + #ifdef HAVE_CONFIG_H #include #endif +#include + #ifdef HAVE_STRING_H #include #endif @@ -32,67 +55,32 @@ #include #endif -#ifdef emacs -#include "blockinput.h" -#endif - -/* If compiling with GCC 2, this file's not needed. Except of course if - the C alloca is explicitly requested. */ -#if defined (USE_C_ALLOCA) || !defined (__GNUC__) || __GNUC__ < 2 - -/* If someone has defined alloca as a macro, - there must be some other way alloca is supposed to work. */ -#ifndef alloca - -#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 -you -lose --- must know STACK_DIRECTION at compile-time -#endif /* STACK_DIRECTION undefined */ -#endif /* static */ -#endif /* emacs */ +/* These variables are used by the ASTRDUP implementation that relies + on C_alloca. */ +#ifdef __cplusplus +extern "C" { +#endif /* __cplusplus */ +const char *libiberty_optr; +char *libiberty_nptr; +unsigned long libiberty_len; +#ifdef __cplusplus +} +#endif /* __cplusplus */ /* 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) -long i00afunc (); +static 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 - #ifndef NULL #define NULL 0 #endif -/* 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 use xmalloc. - - Callers below should use malloc. */ - -#ifndef emacs -#define malloc xmalloc -#endif -extern pointer malloc (); - /* Define STACK_DIRECTION if you know the direction of stack growth for your system; otherwise it will be automatically deduced at run-time. @@ -115,7 +103,7 @@ static int stack_dir; /* 1 or -1 once known. */ #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. */ @@ -168,9 +156,10 @@ 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; +/* @undocumented C_alloca */ + +PTR +C_alloca (size_t size) { auto char probe; /* Probes stack depth: */ register char *depth = ADDRESS_FUNCTION (probe); @@ -186,17 +175,13 @@ alloca (size) { register header *hp; /* Traverses linked list. */ -#ifdef emacs - BLOCK_INPUT; -#endif - for (hp = last_alloca_header; hp != NULL;) if ((STACK_DIR > 0 && hp->h.deep > depth) || (STACK_DIR < 0 && hp->h.deep < depth)) { register header *np = hp->h.next; - free ((pointer) hp); /* Collect garbage. */ + free ((PTR) hp); /* Collect garbage. */ hp = np; /* -> next header. */ } @@ -204,10 +189,6 @@ alloca (size) break; /* Rest are not deeper. */ last_alloca_header = hp; /* -> last valid storage. */ - -#ifdef emacs - UNBLOCK_INPUT; -#endif } if (size == 0) @@ -216,20 +197,20 @@ alloca (size) /* Allocate combined header + user data storage. */ { - register pointer new = malloc (sizeof (header) + size); + register void *new_storage = XNEWVEC (char, sizeof (header) + size); /* Address of header. */ - if (new == 0) + if (new_storage == 0) abort(); - ((header *) new)->h.next = last_alloca_header; - ((header *) new)->h.deep = depth; + ((header *) new_storage)->h.next = last_alloca_header; + ((header *) new_storage)->h.deep = depth; - last_alloca_header = (header *) new; + last_alloca_header = (header *) new_storage; /* User storage begins just after header. */ - return (pointer) ((char *) new + sizeof (header)); + return (PTR) ((char *) new_storage + sizeof (header)); } } @@ -500,6 +481,3 @@ i00afunc (long address) #endif /* not CRAY2 */ #endif /* CRAY */ - -#endif /* no alloca */ -#endif /* not GCC version 2 */