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malloc.c revision 1.20
      1  1.20   thorpej /*	$NetBSD: malloc.c,v 1.20 1999/07/05 21:49:05 thorpej Exp $	*/
      2  1.18   thorpej 
      3   1.1       cgd /*
      4  1.17       tls  * ----------------------------------------------------------------------------
      5  1.17       tls  * "THE BEER-WARE LICENSE" (Revision 42):
      6  1.17       tls  * <phk (at) FreeBSD.ORG> wrote this file.  As long as you retain this notice you
      7  1.17       tls  * can do whatever you want with this stuff. If we meet some day, and you think
      8  1.17       tls  * this stuff is worth it, you can buy me a beer in return.   Poul-Henning Kamp
      9  1.17       tls  * ----------------------------------------------------------------------------
     10   1.1       cgd  *
     11  1.17       tls  * From FreeBSD: malloc.c,v 1.43 1998/09/30 06:13:59 jb
     12   1.1       cgd  *
     13  1.17       tls  */
     14  1.17       tls 
     15  1.17       tls /*
     16  1.19   thorpej  * Defining MALLOC_EXTRA_SANITY will enable extra checks which are related
     17  1.17       tls  * to internal conditions and consistency in malloc.c. This has a
     18  1.17       tls  * noticeable runtime performance hit, and generally will not do you
     19  1.17       tls  * any good unless you fiddle with the internals of malloc or want
     20  1.17       tls  * to catch random pointer corruption as early as possible.
     21  1.17       tls  */
     22  1.17       tls #ifndef MALLOC_EXTRA_SANITY
     23  1.17       tls #undef MALLOC_EXTRA_SANITY
     24   1.5   thorpej #endif
     25   1.1       cgd 
     26   1.1       cgd /*
     27  1.17       tls  * What to use for Junk.  This is the byte value we use to fill with
     28  1.17       tls  * when the 'J' option is enabled.
     29  1.17       tls  */
     30  1.17       tls #define SOME_JUNK	0xd0		/* as in "Duh" :-) */
     31  1.17       tls 
     32  1.17       tls /*
     33  1.17       tls  * The basic parameters you can tweak.
     34  1.17       tls  *
     35  1.17       tls  * malloc_minsize	minimum size of an allocation in bytes.
     36  1.17       tls  *			If this is too small it's too much work
     37  1.17       tls  *			to manage them.  This is also the smallest
     38  1.17       tls  *			unit of alignment used for the storage
     39  1.17       tls  *			returned by malloc/realloc.
     40   1.1       cgd  *
     41   1.1       cgd  */
     42   1.1       cgd 
     43  1.17       tls #if defined(__FreeBSD__)
     44  1.17       tls #   if defined(__i386__)
     45  1.17       tls #       define malloc_minsize		16U
     46  1.17       tls #   endif
     47  1.17       tls #   if defined(__alpha__)
     48  1.17       tls #       define malloc_minsize		16U
     49  1.17       tls #   endif
     50  1.17       tls #   if !defined(__NETBSD_SYSCALLS)
     51  1.17       tls #       define HAS_UTRACE
     52  1.17       tls #   endif
     53  1.17       tls     /*
     54  1.17       tls      * Make malloc/free/realloc thread-safe in libc for use with
     55  1.17       tls      * kernel threads.
     56  1.17       tls      */
     57  1.17       tls #   include "libc_private.h"
     58  1.17       tls #   include "spinlock.h"
     59  1.17       tls     static spinlock_t thread_lock	= _SPINLOCK_INITIALIZER;
     60  1.17       tls #   define THREAD_LOCK()		if (__isthreaded) _SPINLOCK(&thread_lock);
     61  1.17       tls #   define THREAD_UNLOCK()		if (__isthreaded) _SPINUNLOCK(&thread_lock);
     62  1.17       tls #endif /* __FreeBSD__ */
     63  1.17       tls 
     64  1.17       tls #if defined(__NetBSD__)
     65  1.17       tls #   define malloc_minsize               16U
     66  1.17       tls #endif /* __NetBSD__ */
     67  1.17       tls 
     68  1.17       tls #if defined(__sparc__) && defined(sun)
     69  1.17       tls #   define malloc_minsize		16U
     70  1.17       tls #   define MAP_ANON			(0)
     71  1.17       tls     static int fdzero;
     72  1.17       tls #   define MMAP_FD	fdzero
     73  1.17       tls #   define INIT_MMAP() \
     74  1.17       tls 	{ if ((fdzero=open("/dev/zero", O_RDWR, 0000)) == -1) \
     75  1.17       tls 	    wrterror("open of /dev/zero"); }
     76  1.17       tls #endif /* __sparc__ */
     77  1.17       tls 
     78  1.17       tls /* Insert your combination here... */
     79  1.17       tls #if defined(__FOOCPU__) && defined(__BAROS__)
     80  1.17       tls #   define malloc_minsize		16U
     81  1.17       tls #endif /* __FOOCPU__ && __BAROS__ */
     82  1.17       tls 
     83  1.17       tls 
     84  1.17       tls /*
     85  1.17       tls  * No user serviceable parts behind this point.
     86  1.17       tls  */
     87  1.16    kleink #include <sys/types.h>
     88  1.17       tls #include <sys/mman.h>
     89  1.17       tls #include <errno.h>
     90  1.17       tls #include <fcntl.h>
     91  1.17       tls #include <stddef.h>
     92   1.9  christos #include <stdio.h>
     93   1.1       cgd #include <stdlib.h>
     94   1.1       cgd #include <string.h>
     95   1.1       cgd #include <unistd.h>
     96   1.1       cgd 
     97  1.17       tls /*
     98  1.17       tls  * This structure describes a page worth of chunks.
     99  1.17       tls  */
    100  1.17       tls 
    101  1.17       tls struct pginfo {
    102  1.17       tls     struct pginfo	*next;	/* next on the free list */
    103  1.17       tls     void		*page;	/* Pointer to the page */
    104  1.17       tls     u_short		size;	/* size of this page's chunks */
    105  1.17       tls     u_short		shift;	/* How far to shift for this size chunks */
    106  1.17       tls     u_short		free;	/* How many free chunks */
    107  1.17       tls     u_short		total;	/* How many chunk */
    108  1.17       tls     u_int		bits[1]; /* Which chunks are free */
    109  1.17       tls };
    110   1.1       cgd 
    111   1.1       cgd /*
    112  1.17       tls  * This structure describes a number of free pages.
    113  1.17       tls  */
    114  1.17       tls 
    115  1.17       tls struct pgfree {
    116  1.17       tls     struct pgfree	*next;	/* next run of free pages */
    117  1.17       tls     struct pgfree	*prev;	/* prev run of free pages */
    118  1.17       tls     void		*page;	/* pointer to free pages */
    119  1.17       tls     void		*end;	/* pointer to end of free pages */
    120  1.17       tls     size_t		size;	/* number of bytes free */
    121   1.1       cgd };
    122   1.1       cgd 
    123  1.17       tls /*
    124  1.17       tls  * How many bits per u_int in the bitmap.
    125  1.17       tls  * Change only if not 8 bits/byte
    126  1.17       tls  */
    127  1.17       tls #define	MALLOC_BITS	(8*sizeof(u_int))
    128  1.17       tls 
    129  1.17       tls /*
    130  1.17       tls  * Magic values to put in the page_directory
    131  1.17       tls  */
    132  1.17       tls #define MALLOC_NOT_MINE	((struct pginfo*) 0)
    133  1.17       tls #define MALLOC_FREE 	((struct pginfo*) 1)
    134  1.17       tls #define MALLOC_FIRST	((struct pginfo*) 2)
    135  1.17       tls #define MALLOC_FOLLOW	((struct pginfo*) 3)
    136  1.17       tls #define MALLOC_MAGIC	((struct pginfo*) 4)
    137  1.17       tls 
    138  1.20   thorpej /*
    139  1.20   thorpej  * Page size related parameters, computed at run-time.
    140  1.20   thorpej  */
    141  1.20   thorpej static size_t malloc_pagesize;
    142  1.20   thorpej static size_t malloc_pageshift;
    143  1.20   thorpej static size_t malloc_pagemask;
    144  1.17       tls 
    145  1.17       tls #ifndef malloc_minsize
    146  1.17       tls #define malloc_minsize			16U
    147  1.17       tls #endif
    148  1.17       tls 
    149  1.17       tls #ifndef malloc_maxsize
    150  1.17       tls #define malloc_maxsize			((malloc_pagesize)>>1)
    151  1.17       tls #endif
    152  1.17       tls 
    153  1.17       tls #define pageround(foo) (((foo) + (malloc_pagemask))&(~(malloc_pagemask)))
    154  1.17       tls #define ptr2index(foo) (((u_long)(foo) >> malloc_pageshift)-malloc_origo)
    155   1.1       cgd 
    156  1.17       tls #ifndef THREAD_LOCK
    157  1.17       tls #define THREAD_LOCK()
    158  1.17       tls #endif
    159   1.1       cgd 
    160  1.17       tls #ifndef THREAD_UNLOCK
    161  1.17       tls #define THREAD_UNLOCK()
    162  1.16    kleink #endif
    163  1.16    kleink 
    164  1.17       tls #ifndef MMAP_FD
    165  1.17       tls #define MMAP_FD (-1)
    166   1.1       cgd #endif
    167   1.1       cgd 
    168  1.17       tls #ifndef INIT_MMAP
    169  1.17       tls #define INIT_MMAP()
    170  1.18   thorpej #endif
    171  1.18   thorpej 
    172  1.18   thorpej #ifndef MADV_FREE
    173  1.18   thorpej #define MADV_FREE MADV_DONTNEED
    174   1.9  christos #endif
    175   1.9  christos 
    176  1.17       tls /* Set when initialization has been done */
    177  1.17       tls static unsigned malloc_started;
    178  1.17       tls 
    179  1.17       tls /* Recusion flag for public interface. */
    180  1.17       tls static int malloc_active;
    181  1.17       tls 
    182  1.17       tls /* Number of free pages we cache */
    183  1.17       tls static unsigned malloc_cache = 16;
    184  1.17       tls 
    185  1.17       tls /* The offset from pagenumber to index into the page directory */
    186  1.17       tls static u_long malloc_origo;
    187  1.17       tls 
    188  1.17       tls /* The last index in the page directory we care about */
    189  1.17       tls static u_long last_index;
    190  1.17       tls 
    191  1.17       tls /* Pointer to page directory. Allocated "as if with" malloc */
    192  1.17       tls static struct	pginfo **page_dir;
    193  1.17       tls 
    194  1.17       tls /* How many slots in the page directory */
    195  1.17       tls static unsigned	malloc_ninfo;
    196  1.17       tls 
    197  1.17       tls /* Free pages line up here */
    198  1.17       tls static struct pgfree free_list;
    199  1.17       tls 
    200  1.17       tls /* Abort(), user doesn't handle problems.  */
    201  1.17       tls static int malloc_abort;
    202  1.17       tls 
    203  1.17       tls /* Are we trying to die ?  */
    204  1.17       tls static int suicide;
    205  1.17       tls 
    206  1.17       tls /* always realloc ?  */
    207  1.17       tls static int malloc_realloc;
    208   1.9  christos 
    209  1.17       tls /* pass the kernel a hint on free pages ?  */
    210  1.17       tls static int malloc_hint = 1;
    211  1.17       tls 
    212  1.17       tls /* xmalloc behaviour ?  */
    213  1.17       tls static int malloc_xmalloc;
    214  1.17       tls 
    215  1.17       tls /* sysv behaviour for malloc(0) ?  */
    216  1.17       tls static int malloc_sysv;
    217  1.17       tls 
    218  1.17       tls /* zero fill ?  */
    219  1.17       tls static int malloc_zero;
    220  1.17       tls 
    221  1.17       tls /* junk fill ?  */
    222  1.17       tls static int malloc_junk;
    223  1.17       tls 
    224  1.17       tls #ifdef HAS_UTRACE
    225  1.17       tls 
    226  1.17       tls /* utrace ?  */
    227  1.17       tls static int malloc_utrace;
    228  1.17       tls 
    229  1.17       tls struct ut { void *p; size_t s; void *r; };
    230  1.17       tls 
    231  1.17       tls void utrace __P((struct ut *, int));
    232  1.17       tls 
    233  1.17       tls #define UTRACE(a, b, c) \
    234  1.17       tls 	if (malloc_utrace) \
    235  1.17       tls 		{struct ut u; u.p=a; u.s = b; u.r=c; utrace(&u, sizeof u);}
    236  1.17       tls #else /* !HAS_UTRACE */
    237  1.17       tls #define UTRACE(a,b,c)
    238  1.17       tls #endif /* HAS_UTRACE */
    239  1.17       tls 
    240  1.17       tls /* my last break. */
    241  1.17       tls static void *malloc_brk;
    242  1.17       tls 
    243  1.17       tls /* one location cache for free-list holders */
    244  1.17       tls static struct pgfree *px;
    245  1.17       tls 
    246  1.17       tls /* compile-time options */
    247  1.17       tls char *malloc_options;
    248  1.17       tls 
    249  1.17       tls /* Name of the current public function */
    250  1.17       tls static char *malloc_func;
    251  1.17       tls 
    252  1.17       tls /* Macro for mmap */
    253  1.17       tls #define MMAP(size) \
    254  1.17       tls 	mmap(0, (size), PROT_READ|PROT_WRITE, MAP_ANON|MAP_PRIVATE, \
    255  1.17       tls 	    MMAP_FD, 0);
    256   1.9  christos 
    257  1.16    kleink /*
    258  1.17       tls  * Necessary function declarations
    259  1.16    kleink  */
    260  1.17       tls static int extend_pgdir(u_long index);
    261  1.17       tls static void *imalloc(size_t size);
    262  1.17       tls static void ifree(void *ptr);
    263  1.17       tls static void *irealloc(void *ptr, size_t size);
    264  1.17       tls 
    265  1.17       tls extern char *__progname;
    266  1.17       tls 
    267  1.17       tls static void
    268  1.17       tls wrterror(char *p)
    269  1.17       tls {
    270  1.17       tls     char *q = " error: ";
    271  1.17       tls     write(STDERR_FILENO, __progname, strlen(__progname));
    272  1.17       tls     write(STDERR_FILENO, malloc_func, strlen(malloc_func));
    273  1.17       tls     write(STDERR_FILENO, q, strlen(q));
    274  1.17       tls     write(STDERR_FILENO, p, strlen(p));
    275  1.17       tls     suicide = 1;
    276  1.17       tls     abort();
    277  1.17       tls }
    278  1.17       tls 
    279  1.16    kleink static void
    280  1.17       tls wrtwarning(char *p)
    281   1.1       cgd {
    282  1.17       tls     char *q = " warning: ";
    283  1.17       tls     if (malloc_abort)
    284  1.17       tls 	wrterror(p);
    285  1.17       tls     write(STDERR_FILENO, __progname, strlen(__progname));
    286  1.17       tls     write(STDERR_FILENO, malloc_func, strlen(malloc_func));
    287  1.17       tls     write(STDERR_FILENO, q, strlen(q));
    288  1.17       tls     write(STDERR_FILENO, p, strlen(p));
    289  1.17       tls }
    290  1.17       tls 
    291  1.16    kleink 
    292  1.17       tls /*
    293  1.17       tls  * Allocate a number of pages from the OS
    294  1.17       tls  */
    295  1.17       tls static void *
    296  1.17       tls map_pages(int pages)
    297  1.17       tls {
    298  1.17       tls     caddr_t result, tail;
    299  1.16    kleink 
    300  1.17       tls     result = (caddr_t)pageround((u_long)sbrk(0));
    301  1.17       tls     tail = result + (pages << malloc_pageshift);
    302  1.17       tls 
    303  1.17       tls     if (brk(tail)) {
    304  1.19   thorpej #ifdef MALLOC_EXTRA_SANITY
    305  1.17       tls 	wrterror("(ES): map_pages fails\n");
    306  1.19   thorpej #endif /* MALLOC_EXTRA_SANITY */
    307  1.17       tls 	return 0;
    308  1.17       tls     }
    309  1.17       tls 
    310  1.17       tls     last_index = ptr2index(tail) - 1;
    311  1.17       tls     malloc_brk = tail;
    312  1.17       tls 
    313  1.17       tls     if ((last_index+1) >= malloc_ninfo && !extend_pgdir(last_index))
    314  1.17       tls 	return 0;;
    315  1.16    kleink 
    316  1.17       tls     return result;
    317   1.1       cgd }
    318   1.1       cgd 
    319  1.17       tls /*
    320  1.17       tls  * Extend page directory
    321  1.17       tls  */
    322  1.17       tls static int
    323  1.17       tls extend_pgdir(u_long index)
    324   1.1       cgd {
    325  1.17       tls     struct  pginfo **new, **old;
    326  1.17       tls     int i, oldlen;
    327   1.1       cgd 
    328  1.17       tls     /* Make it this many pages */
    329  1.17       tls     i = index * sizeof *page_dir;
    330  1.17       tls     i /= malloc_pagesize;
    331  1.17       tls     i += 2;
    332  1.17       tls 
    333  1.17       tls     /* remember the old mapping size */
    334  1.17       tls     oldlen = malloc_ninfo * sizeof *page_dir;
    335  1.17       tls 
    336  1.17       tls     /*
    337  1.17       tls      * NOTE: we allocate new pages and copy the directory rather than tempt
    338  1.17       tls      * fate by trying to "grow" the region.. There is nothing to prevent
    339  1.17       tls      * us from accidently re-mapping space that's been allocated by our caller
    340  1.17       tls      * via dlopen() or other mmap().
    341  1.17       tls      *
    342  1.17       tls      * The copy problem is not too bad, as there is 4K of page index per
    343  1.17       tls      * 4MB of malloc arena.
    344  1.17       tls      *
    345  1.17       tls      * We can totally avoid the copy if we open a file descriptor to associate
    346  1.17       tls      * the anon mappings with.  Then, when we remap the pages at the new
    347  1.17       tls      * address, the old pages will be "magically" remapped..  But this means
    348  1.17       tls      * keeping open a "secret" file descriptor.....
    349  1.17       tls      */
    350  1.17       tls 
    351  1.17       tls     /* Get new pages */
    352  1.17       tls     new = (struct pginfo**) MMAP(i * malloc_pagesize);
    353  1.17       tls     if (new == (struct pginfo **)-1)
    354  1.17       tls 	return 0;
    355  1.17       tls 
    356  1.17       tls     /* Copy the old stuff */
    357  1.17       tls     memcpy(new, page_dir,
    358  1.17       tls 	    malloc_ninfo * sizeof *page_dir);
    359  1.17       tls 
    360  1.17       tls     /* register the new size */
    361  1.17       tls     malloc_ninfo = i * malloc_pagesize / sizeof *page_dir;
    362  1.17       tls 
    363  1.17       tls     /* swap the pointers */
    364  1.17       tls     old = page_dir;
    365  1.17       tls     page_dir = new;
    366  1.17       tls 
    367  1.17       tls     /* Now free the old stuff */
    368  1.17       tls     munmap(old, oldlen);
    369  1.17       tls     return 1;
    370  1.17       tls }
    371  1.16    kleink 
    372  1.17       tls /*
    373  1.17       tls  * Initialize the world
    374  1.17       tls  */
    375  1.17       tls static void
    376  1.17       tls malloc_init (void)
    377  1.17       tls {
    378  1.17       tls     char *p, b[64];
    379  1.17       tls     int i, j;
    380  1.17       tls     int errnosave;
    381  1.20   thorpej 
    382  1.20   thorpej     /*
    383  1.20   thorpej      * Compute page-size related variables.
    384  1.20   thorpej      */
    385  1.20   thorpej     malloc_pagesize = sysconf(_SC_PAGESIZE);
    386  1.20   thorpej     malloc_pagemask = malloc_pagesize - 1;
    387  1.20   thorpej     for (malloc_pageshift = 0;
    388  1.20   thorpej 	 (1UL << malloc_pageshift) != malloc_pagesize;
    389  1.20   thorpej 	 malloc_pageshift++)
    390  1.20   thorpej 	/* nothing */ ;
    391  1.17       tls 
    392  1.17       tls     INIT_MMAP();
    393  1.17       tls 
    394  1.19   thorpej #ifdef MALLOC_EXTRA_SANITY
    395  1.17       tls     malloc_junk = 1;
    396  1.19   thorpej #endif /* MALLOC_EXTRA_SANITY */
    397  1.17       tls 
    398  1.17       tls     for (i = 0; i < 3; i++) {
    399  1.17       tls 	if (i == 0) {
    400  1.17       tls 	    errnosave = errno;
    401  1.17       tls 	    j = readlink("/etc/malloc.conf", b, sizeof b - 1);
    402  1.17       tls 	    errno = errnosave;
    403  1.17       tls 	    if (j <= 0)
    404  1.17       tls 		continue;
    405  1.17       tls 	    b[j] = '\0';
    406  1.17       tls 	    p = b;
    407  1.17       tls 	} else if (i == 1) {
    408  1.17       tls 	    p = getenv("MALLOC_OPTIONS");
    409  1.17       tls 	} else {
    410  1.17       tls 	    p = malloc_options;
    411   1.1       cgd 	}
    412  1.17       tls 	for (; p && *p; p++) {
    413  1.17       tls 	    switch (*p) {
    414  1.17       tls 		case '>': malloc_cache   <<= 1; break;
    415  1.17       tls 		case '<': malloc_cache   >>= 1; break;
    416  1.17       tls 		case 'a': malloc_abort   = 0; break;
    417  1.17       tls 		case 'A': malloc_abort   = 1; break;
    418  1.17       tls 		case 'h': malloc_hint    = 0; break;
    419  1.17       tls 		case 'H': malloc_hint    = 1; break;
    420  1.17       tls 		case 'r': malloc_realloc = 0; break;
    421  1.17       tls 		case 'R': malloc_realloc = 1; break;
    422  1.17       tls 		case 'j': malloc_junk    = 0; break;
    423  1.17       tls 		case 'J': malloc_junk    = 1; break;
    424  1.17       tls #ifdef HAS_UTRACE
    425  1.17       tls 		case 'u': malloc_utrace  = 0; break;
    426  1.17       tls 		case 'U': malloc_utrace  = 1; break;
    427  1.17       tls #endif
    428  1.17       tls 		case 'v': malloc_sysv    = 0; break;
    429  1.17       tls 		case 'V': malloc_sysv    = 1; break;
    430  1.17       tls 		case 'x': malloc_xmalloc = 0; break;
    431  1.17       tls 		case 'X': malloc_xmalloc = 1; break;
    432  1.17       tls 		case 'z': malloc_zero    = 0; break;
    433  1.17       tls 		case 'Z': malloc_zero    = 1; break;
    434  1.17       tls 		default:
    435  1.17       tls 		    j = malloc_abort;
    436  1.17       tls 		    malloc_abort = 0;
    437  1.17       tls 		    wrtwarning("unknown char in MALLOC_OPTIONS\n");
    438  1.17       tls 		    malloc_abort = j;
    439  1.17       tls 		    break;
    440  1.17       tls 	    }
    441   1.1       cgd 	}
    442  1.17       tls     }
    443  1.17       tls 
    444  1.17       tls     UTRACE(0, 0, 0);
    445  1.17       tls 
    446  1.17       tls     /*
    447  1.17       tls      * We want junk in the entire allocation, and zero only in the part
    448  1.17       tls      * the user asked for.
    449  1.17       tls      */
    450  1.17       tls     if (malloc_zero)
    451  1.17       tls 	malloc_junk=1;
    452  1.17       tls 
    453  1.17       tls     /*
    454  1.17       tls      * If we run with junk (or implicitly from above: zero), we want to
    455  1.17       tls      * force realloc() to get new storage, so we can DTRT with it.
    456  1.17       tls      */
    457  1.17       tls     if (malloc_junk)
    458  1.17       tls 	malloc_realloc=1;
    459  1.17       tls 
    460  1.17       tls     /* Allocate one page for the page directory */
    461  1.17       tls     page_dir = (struct pginfo **) MMAP(malloc_pagesize);
    462  1.17       tls 
    463  1.17       tls     if (page_dir == (struct pginfo **) -1)
    464  1.17       tls 	wrterror("mmap(2) failed, check limits.\n");
    465  1.17       tls 
    466  1.17       tls     /*
    467  1.17       tls      * We need a maximum of malloc_pageshift buckets, steal these from the
    468  1.17       tls      * front of the page_directory;
    469  1.17       tls      */
    470  1.17       tls     malloc_origo = ((u_long)pageround((u_long)sbrk(0))) >> malloc_pageshift;
    471  1.17       tls     malloc_origo -= malloc_pageshift;
    472  1.17       tls 
    473  1.17       tls     malloc_ninfo = malloc_pagesize / sizeof *page_dir;
    474  1.17       tls 
    475  1.17       tls     /* Recalculate the cache size in bytes, and make sure it's nonzero */
    476  1.17       tls 
    477  1.17       tls     if (!malloc_cache)
    478  1.17       tls 	malloc_cache++;
    479  1.17       tls 
    480  1.17       tls     malloc_cache <<= malloc_pageshift;
    481  1.17       tls 
    482  1.17       tls     /*
    483  1.17       tls      * This is a nice hack from Kaleb Keithly (kaleb (at) x.org).
    484  1.17       tls      * We can sbrk(2) further back when we keep this on a low address.
    485  1.17       tls      */
    486  1.17       tls     px = (struct pgfree *) imalloc (sizeof *px);
    487  1.17       tls 
    488  1.17       tls     /* Been here, done that */
    489  1.17       tls     malloc_started++;
    490  1.17       tls }
    491  1.17       tls 
    492  1.17       tls /*
    493  1.17       tls  * Allocate a number of complete pages
    494  1.17       tls  */
    495  1.17       tls static void *
    496  1.17       tls malloc_pages(size_t size)
    497  1.17       tls {
    498  1.17       tls     void *p, *delay_free = 0;
    499  1.17       tls     int i;
    500  1.17       tls     struct pgfree *pf;
    501  1.17       tls     u_long index;
    502  1.17       tls 
    503  1.17       tls     size = pageround(size);
    504  1.17       tls 
    505  1.17       tls     p = 0;
    506  1.17       tls 
    507  1.17       tls     /* Look for free pages before asking for more */
    508  1.17       tls     for(pf = free_list.next; pf; pf = pf->next) {
    509  1.17       tls 
    510  1.19   thorpej #ifdef MALLOC_EXTRA_SANITY
    511  1.17       tls 	if (pf->size & malloc_pagemask)
    512  1.17       tls 	    wrterror("(ES): junk length entry on free_list\n");
    513  1.17       tls 	if (!pf->size)
    514  1.17       tls 	    wrterror("(ES): zero length entry on free_list\n");
    515  1.17       tls 	if (pf->page == pf->end)
    516  1.17       tls 	    wrterror("(ES): zero entry on free_list\n");
    517  1.17       tls 	if (pf->page > pf->end)
    518  1.17       tls 	    wrterror("(ES): sick entry on free_list\n");
    519  1.17       tls 	if ((void*)pf->page >= (void*)sbrk(0))
    520  1.17       tls 	    wrterror("(ES): entry on free_list past brk\n");
    521  1.17       tls 	if (page_dir[ptr2index(pf->page)] != MALLOC_FREE)
    522  1.17       tls 	    wrterror("(ES): non-free first page on free-list\n");
    523  1.17       tls 	if (page_dir[ptr2index(pf->end)-1] != MALLOC_FREE)
    524  1.17       tls 	    wrterror("(ES): non-free last page on free-list\n");
    525  1.19   thorpej #endif /* MALLOC_EXTRA_SANITY */
    526  1.17       tls 
    527  1.17       tls 	if (pf->size < size)
    528  1.17       tls 	    continue;
    529  1.17       tls 
    530  1.17       tls 	if (pf->size == size) {
    531  1.17       tls 	    p = pf->page;
    532  1.17       tls 	    if (pf->next)
    533  1.17       tls 		    pf->next->prev = pf->prev;
    534  1.17       tls 	    pf->prev->next = pf->next;
    535  1.17       tls 	    delay_free = pf;
    536  1.17       tls 	    break;
    537  1.17       tls 	}
    538  1.17       tls 
    539  1.17       tls 	p = pf->page;
    540  1.17       tls 	pf->page = (char *)pf->page + size;
    541  1.17       tls 	pf->size -= size;
    542  1.17       tls 	break;
    543  1.17       tls     }
    544  1.17       tls 
    545  1.19   thorpej #ifdef MALLOC_EXTRA_SANITY
    546  1.17       tls     if (p && page_dir[ptr2index(p)] != MALLOC_FREE)
    547  1.17       tls 	wrterror("(ES): allocated non-free page on free-list\n");
    548  1.19   thorpej #endif /* MALLOC_EXTRA_SANITY */
    549  1.17       tls 
    550  1.17       tls     size >>= malloc_pageshift;
    551  1.17       tls 
    552  1.17       tls     /* Map new pages */
    553  1.17       tls     if (!p)
    554  1.17       tls 	p = map_pages(size);
    555  1.17       tls 
    556  1.17       tls     if (p) {
    557  1.17       tls 
    558  1.17       tls 	index = ptr2index(p);
    559  1.17       tls 	page_dir[index] = MALLOC_FIRST;
    560  1.17       tls 	for (i=1;i<size;i++)
    561  1.17       tls 	    page_dir[index+i] = MALLOC_FOLLOW;
    562  1.17       tls 
    563  1.17       tls 	if (malloc_junk)
    564  1.17       tls 	    memset(p, SOME_JUNK, size << malloc_pageshift);
    565  1.17       tls     }
    566  1.17       tls 
    567  1.17       tls     if (delay_free) {
    568  1.17       tls 	if (!px)
    569  1.17       tls 	    px = delay_free;
    570  1.17       tls 	else
    571  1.17       tls 	    ifree(delay_free);
    572  1.17       tls     }
    573  1.17       tls 
    574  1.17       tls     return p;
    575  1.17       tls }
    576  1.17       tls 
    577  1.17       tls /*
    578  1.17       tls  * Allocate a page of fragments
    579  1.17       tls  */
    580  1.17       tls 
    581  1.17       tls static __inline__ int
    582  1.17       tls malloc_make_chunks(int bits)
    583  1.17       tls {
    584  1.17       tls     struct  pginfo *bp;
    585  1.17       tls     void *pp;
    586  1.17       tls     int i, k, l;
    587  1.17       tls 
    588  1.17       tls     /* Allocate a new bucket */
    589  1.17       tls     pp = malloc_pages(malloc_pagesize);
    590  1.17       tls     if (!pp)
    591  1.17       tls 	return 0;
    592  1.17       tls 
    593  1.17       tls     /* Find length of admin structure */
    594  1.17       tls     l = offsetof(struct pginfo, bits[0]);
    595  1.17       tls     l += sizeof bp->bits[0] *
    596  1.17       tls 	(((malloc_pagesize >> bits)+MALLOC_BITS-1) / MALLOC_BITS);
    597  1.17       tls 
    598  1.17       tls     /* Don't waste more than two chunks on this */
    599  1.17       tls     if ((1<<(bits)) <= l+l) {
    600  1.17       tls 	bp = (struct  pginfo *)pp;
    601  1.17       tls     } else {
    602  1.17       tls 	bp = (struct  pginfo *)imalloc(l);
    603  1.17       tls 	if (!bp) {
    604  1.17       tls 	    ifree(pp);
    605  1.17       tls 	    return 0;
    606   1.1       cgd 	}
    607  1.17       tls     }
    608  1.17       tls 
    609  1.17       tls     bp->size = (1<<bits);
    610  1.17       tls     bp->shift = bits;
    611  1.17       tls     bp->total = bp->free = malloc_pagesize >> bits;
    612  1.17       tls     bp->page = pp;
    613  1.17       tls 
    614  1.17       tls     /* set all valid bits in the bitmap */
    615  1.17       tls     k = bp->total;
    616  1.17       tls     i = 0;
    617  1.17       tls 
    618  1.17       tls     /* Do a bunch at a time */
    619  1.17       tls     for(;k-i >= MALLOC_BITS; i += MALLOC_BITS)
    620  1.17       tls 	bp->bits[i / MALLOC_BITS] = ~0;
    621  1.17       tls 
    622  1.17       tls     for(; i < k; i++)
    623  1.17       tls         bp->bits[i/MALLOC_BITS] |= 1<<(i%MALLOC_BITS);
    624  1.17       tls 
    625  1.17       tls     if (bp == bp->page) {
    626  1.17       tls 	/* Mark the ones we stole for ourselves */
    627  1.17       tls 	for(i=0;l > 0;i++) {
    628  1.17       tls 	    bp->bits[i/MALLOC_BITS] &= ~(1<<(i%MALLOC_BITS));
    629  1.17       tls 	    bp->free--;
    630  1.17       tls 	    bp->total--;
    631  1.17       tls 	    l -= (1 << bits);
    632   1.1       cgd 	}
    633  1.17       tls     }
    634  1.17       tls 
    635  1.17       tls     /* MALLOC_LOCK */
    636  1.17       tls 
    637  1.17       tls     page_dir[ptr2index(pp)] = bp;
    638  1.17       tls 
    639  1.17       tls     bp->next = page_dir[bits];
    640  1.17       tls     page_dir[bits] = bp;
    641  1.17       tls 
    642  1.17       tls     /* MALLOC_UNLOCK */
    643  1.17       tls 
    644  1.17       tls     return 1;
    645   1.1       cgd }
    646   1.1       cgd 
    647   1.1       cgd /*
    648  1.17       tls  * Allocate a fragment
    649   1.1       cgd  */
    650  1.17       tls static void *
    651  1.17       tls malloc_bytes(size_t size)
    652   1.1       cgd {
    653  1.17       tls     int i,j;
    654  1.17       tls     u_int u;
    655  1.17       tls     struct  pginfo *bp;
    656  1.17       tls     int k;
    657  1.17       tls     u_int *lp;
    658  1.17       tls 
    659  1.17       tls     /* Don't bother with anything less than this */
    660  1.17       tls     if (size < malloc_minsize)
    661  1.17       tls 	size = malloc_minsize;
    662  1.17       tls 
    663  1.17       tls     /* Find the right bucket */
    664  1.17       tls     j = 1;
    665  1.17       tls     i = size-1;
    666  1.17       tls     while (i >>= 1)
    667  1.17       tls 	j++;
    668  1.17       tls 
    669  1.17       tls     /* If it's empty, make a page more of that size chunks */
    670  1.17       tls     if (!page_dir[j] && !malloc_make_chunks(j))
    671  1.17       tls 	return 0;
    672  1.17       tls 
    673  1.17       tls     bp = page_dir[j];
    674  1.17       tls 
    675  1.17       tls     /* Find first word of bitmap which isn't empty */
    676  1.17       tls     for (lp = bp->bits; !*lp; lp++)
    677  1.17       tls 	;
    678  1.17       tls 
    679  1.17       tls     /* Find that bit, and tweak it */
    680  1.17       tls     u = 1;
    681  1.17       tls     k = 0;
    682  1.17       tls     while (!(*lp & u)) {
    683  1.17       tls 	u += u;
    684  1.17       tls 	k++;
    685  1.17       tls     }
    686  1.17       tls     *lp ^= u;
    687  1.17       tls 
    688  1.17       tls     /* If there are no more free, remove from free-list */
    689  1.17       tls     if (!--bp->free) {
    690  1.17       tls 	page_dir[j] = bp->next;
    691  1.17       tls 	bp->next = 0;
    692  1.17       tls     }
    693  1.17       tls 
    694  1.17       tls     /* Adjust to the real offset of that chunk */
    695  1.17       tls     k += (lp-bp->bits)*MALLOC_BITS;
    696  1.17       tls     k <<= bp->shift;
    697  1.17       tls 
    698  1.17       tls     if (malloc_junk)
    699  1.17       tls 	memset((u_char*)bp->page + k, SOME_JUNK, bp->size);
    700   1.1       cgd 
    701  1.17       tls     return (u_char *)bp->page + k;
    702   1.1       cgd }
    703   1.1       cgd 
    704  1.17       tls /*
    705  1.17       tls  * Allocate a piece of memory
    706  1.17       tls  */
    707  1.17       tls static void *
    708  1.17       tls imalloc(size_t size)
    709  1.17       tls {
    710  1.17       tls     void *result;
    711  1.17       tls 
    712  1.17       tls     if (suicide)
    713  1.17       tls 	abort();
    714  1.17       tls 
    715  1.17       tls     if ((size + malloc_pagesize) < size)	/* Check for overflow */
    716  1.17       tls 	result = 0;
    717  1.17       tls     else if (size <= malloc_maxsize)
    718  1.17       tls 	result =  malloc_bytes(size);
    719  1.17       tls     else
    720  1.17       tls 	result =  malloc_pages(size);
    721  1.17       tls 
    722  1.17       tls     if (malloc_abort && !result)
    723  1.17       tls 	wrterror("allocation failed.\n");
    724  1.17       tls 
    725  1.17       tls     if (malloc_zero && result)
    726  1.17       tls 	memset(result, 0, size);
    727  1.17       tls 
    728  1.17       tls     return result;
    729   1.1       cgd }
    730   1.1       cgd 
    731   1.1       cgd /*
    732  1.17       tls  * Change the size of an allocation.
    733   1.1       cgd  */
    734  1.17       tls static void *
    735  1.17       tls irealloc(void *ptr, size_t size)
    736  1.17       tls {
    737  1.17       tls     void *p;
    738  1.17       tls     u_long osize, index;
    739  1.17       tls     struct pginfo **mp;
    740  1.17       tls     int i;
    741  1.17       tls 
    742  1.17       tls     if (suicide)
    743  1.17       tls 	abort();
    744  1.17       tls 
    745  1.17       tls     index = ptr2index(ptr);
    746   1.1       cgd 
    747  1.17       tls     if (index < malloc_pageshift) {
    748  1.17       tls 	wrtwarning("junk pointer, too low to make sense.\n");
    749  1.17       tls 	return 0;
    750  1.17       tls     }
    751  1.17       tls 
    752  1.17       tls     if (index > last_index) {
    753  1.17       tls 	wrtwarning("junk pointer, too high to make sense.\n");
    754  1.17       tls 	return 0;
    755  1.17       tls     }
    756  1.17       tls 
    757  1.17       tls     mp = &page_dir[index];
    758  1.17       tls 
    759  1.17       tls     if (*mp == MALLOC_FIRST) {			/* Page allocation */
    760  1.17       tls 
    761  1.17       tls 	/* Check the pointer */
    762  1.17       tls 	if ((u_long)ptr & malloc_pagemask) {
    763  1.17       tls 	    wrtwarning("modified (page-) pointer.\n");
    764  1.17       tls 	    return 0;
    765  1.17       tls 	}
    766  1.17       tls 
    767  1.17       tls 	/* Find the size in bytes */
    768  1.17       tls 	for (osize = malloc_pagesize; *++mp == MALLOC_FOLLOW;)
    769  1.17       tls 	    osize += malloc_pagesize;
    770  1.17       tls 
    771  1.17       tls         if (!malloc_realloc && 			/* unless we have to, */
    772  1.17       tls 	  size <= osize && 			/* .. or are too small, */
    773  1.17       tls 	  size > (osize - malloc_pagesize)) {	/* .. or can free a page, */
    774  1.17       tls 	    return ptr;				/* don't do anything. */
    775   1.6       jtc 	}
    776  1.17       tls 
    777  1.17       tls     } else if (*mp >= MALLOC_MAGIC) {		/* Chunk allocation */
    778  1.17       tls 
    779  1.17       tls 	/* Check the pointer for sane values */
    780  1.17       tls 	if (((u_long)ptr & ((*mp)->size-1))) {
    781  1.17       tls 	    wrtwarning("modified (chunk-) pointer.\n");
    782  1.17       tls 	    return 0;
    783   1.1       cgd 	}
    784  1.17       tls 
    785  1.17       tls 	/* Find the chunk index in the page */
    786  1.17       tls 	i = ((u_long)ptr & malloc_pagemask) >> (*mp)->shift;
    787  1.17       tls 
    788  1.17       tls 	/* Verify that it isn't a free chunk already */
    789  1.17       tls         if ((*mp)->bits[i/MALLOC_BITS] & (1<<(i%MALLOC_BITS))) {
    790  1.17       tls 	    wrtwarning("chunk is already free.\n");
    791  1.17       tls 	    return 0;
    792  1.16    kleink 	}
    793  1.17       tls 
    794  1.17       tls 	osize = (*mp)->size;
    795  1.17       tls 
    796  1.17       tls 	if (!malloc_realloc &&		/* Unless we have to, */
    797  1.17       tls 	  size < osize && 		/* ..or are too small, */
    798  1.17       tls 	  (size > osize/2 ||	 	/* ..or could use a smaller size, */
    799  1.17       tls 	  osize == malloc_minsize)) {	/* ..(if there is one) */
    800  1.17       tls 	    return ptr;			/* ..Don't do anything */
    801   1.1       cgd 	}
    802  1.17       tls 
    803  1.17       tls     } else {
    804  1.17       tls 	wrtwarning("pointer to wrong page.\n");
    805  1.17       tls 	return 0;
    806  1.17       tls     }
    807  1.17       tls 
    808  1.17       tls     p = imalloc(size);
    809  1.17       tls 
    810  1.17       tls     if (p) {
    811  1.17       tls 	/* copy the lesser of the two sizes, and free the old one */
    812  1.17       tls 	if (!size || !osize)
    813  1.17       tls 	    ;
    814  1.17       tls 	else if (osize < size)
    815  1.17       tls 	    memcpy(p, ptr, osize);
    816  1.17       tls 	else
    817  1.17       tls 	    memcpy(p, ptr, size);
    818  1.17       tls 	ifree(ptr);
    819  1.17       tls     }
    820  1.17       tls     return p;
    821   1.1       cgd }
    822   1.1       cgd 
    823   1.1       cgd /*
    824  1.17       tls  * Free a sequence of pages
    825   1.1       cgd  */
    826  1.17       tls 
    827  1.17       tls static __inline__ void
    828  1.17       tls free_pages(void *ptr, int index, struct pginfo *info)
    829  1.17       tls {
    830  1.17       tls     int i;
    831  1.17       tls     struct pgfree *pf, *pt=0;
    832  1.17       tls     u_long l;
    833  1.17       tls     void *tail;
    834  1.17       tls 
    835  1.17       tls     if (info == MALLOC_FREE) {
    836  1.17       tls 	wrtwarning("page is already free.\n");
    837  1.17       tls 	return;
    838  1.17       tls     }
    839  1.17       tls 
    840  1.17       tls     if (info != MALLOC_FIRST) {
    841  1.17       tls 	wrtwarning("pointer to wrong page.\n");
    842  1.17       tls 	return;
    843  1.17       tls     }
    844  1.17       tls 
    845  1.17       tls     if ((u_long)ptr & malloc_pagemask) {
    846  1.17       tls 	wrtwarning("modified (page-) pointer.\n");
    847  1.17       tls 	return;
    848  1.17       tls     }
    849  1.17       tls 
    850  1.17       tls     /* Count how many pages and mark them free at the same time */
    851  1.17       tls     page_dir[index] = MALLOC_FREE;
    852  1.17       tls     for (i = 1; page_dir[index+i] == MALLOC_FOLLOW; i++)
    853  1.17       tls 	page_dir[index + i] = MALLOC_FREE;
    854  1.17       tls 
    855  1.17       tls     l = i << malloc_pageshift;
    856  1.17       tls 
    857  1.17       tls     if (malloc_junk)
    858  1.17       tls 	memset(ptr, SOME_JUNK, l);
    859  1.17       tls 
    860  1.17       tls     if (malloc_hint)
    861  1.17       tls 	madvise(ptr, l, MADV_FREE);
    862  1.17       tls 
    863  1.17       tls     tail = (char *)ptr+l;
    864  1.17       tls 
    865  1.17       tls     /* add to free-list */
    866  1.17       tls     if (!px)
    867  1.17       tls 	px = imalloc(sizeof *pt);	/* This cannot fail... */
    868  1.17       tls     px->page = ptr;
    869  1.17       tls     px->end =  tail;
    870  1.17       tls     px->size = l;
    871  1.17       tls     if (!free_list.next) {
    872  1.17       tls 
    873  1.17       tls 	/* Nothing on free list, put this at head */
    874  1.17       tls 	px->next = free_list.next;
    875  1.17       tls 	px->prev = &free_list;
    876  1.17       tls 	free_list.next = px;
    877  1.17       tls 	pf = px;
    878  1.17       tls 	px = 0;
    879  1.17       tls 
    880  1.17       tls     } else {
    881  1.17       tls 
    882  1.17       tls 	/* Find the right spot, leave pf pointing to the modified entry. */
    883  1.17       tls 	tail = (char *)ptr+l;
    884  1.17       tls 
    885  1.17       tls 	for(pf = free_list.next; pf->end < ptr && pf->next; pf = pf->next)
    886  1.17       tls 	    ; /* Race ahead here */
    887  1.17       tls 
    888  1.17       tls 	if (pf->page > tail) {
    889  1.17       tls 	    /* Insert before entry */
    890  1.17       tls 	    px->next = pf;
    891  1.17       tls 	    px->prev = pf->prev;
    892  1.17       tls 	    pf->prev = px;
    893  1.17       tls 	    px->prev->next = px;
    894  1.17       tls 	    pf = px;
    895  1.17       tls 	    px = 0;
    896  1.17       tls 	} else if (pf->end == ptr ) {
    897  1.17       tls 	    /* Append to the previous entry */
    898  1.17       tls 	    pf->end = (char *)pf->end + l;
    899  1.17       tls 	    pf->size += l;
    900  1.17       tls 	    if (pf->next && pf->end == pf->next->page ) {
    901  1.17       tls 		/* And collapse the next too. */
    902  1.17       tls 		pt = pf->next;
    903  1.17       tls 		pf->end = pt->end;
    904  1.17       tls 		pf->size += pt->size;
    905  1.17       tls 		pf->next = pt->next;
    906  1.17       tls 		if (pf->next)
    907  1.17       tls 		    pf->next->prev = pf;
    908  1.17       tls 	    }
    909  1.17       tls 	} else if (pf->page == tail) {
    910  1.17       tls 	    /* Prepend to entry */
    911  1.17       tls 	    pf->size += l;
    912  1.17       tls 	    pf->page = ptr;
    913  1.17       tls 	} else if (!pf->next) {
    914  1.17       tls 	    /* Append at tail of chain */
    915  1.17       tls 	    px->next = 0;
    916  1.17       tls 	    px->prev = pf;
    917  1.17       tls 	    pf->next = px;
    918  1.17       tls 	    pf = px;
    919  1.17       tls 	    px = 0;
    920  1.17       tls 	} else {
    921  1.17       tls 	    wrterror("freelist is destroyed.\n");
    922   1.1       cgd 	}
    923  1.17       tls     }
    924  1.17       tls 
    925  1.17       tls     /* Return something to OS ? */
    926  1.17       tls     if (!pf->next &&				/* If we're the last one, */
    927  1.17       tls       pf->size > malloc_cache &&		/* ..and the cache is full, */
    928  1.17       tls       pf->end == malloc_brk &&			/* ..and none behind us, */
    929  1.17       tls       malloc_brk == sbrk(0)) {			/* ..and it's OK to do... */
    930  1.17       tls 
    931  1.17       tls 	/*
    932  1.17       tls 	 * Keep the cache intact.  Notice that the '>' above guarantees that
    933  1.17       tls 	 * the pf will always have at least one page afterwards.
    934  1.17       tls 	 */
    935  1.17       tls 	pf->end = (char *)pf->page + malloc_cache;
    936  1.17       tls 	pf->size = malloc_cache;
    937  1.17       tls 
    938  1.17       tls 	brk(pf->end);
    939  1.17       tls 	malloc_brk = pf->end;
    940  1.17       tls 
    941  1.17       tls 	index = ptr2index(pf->end);
    942  1.17       tls 	last_index = index - 1;
    943  1.17       tls 
    944  1.17       tls 	for(i=index;i <= last_index;)
    945  1.17       tls 	    page_dir[i++] = MALLOC_NOT_MINE;
    946  1.17       tls 
    947  1.17       tls 	/* XXX: We could realloc/shrink the pagedir here I guess. */
    948  1.17       tls     }
    949  1.17       tls     if (pt)
    950  1.17       tls 	ifree(pt);
    951   1.1       cgd }
    952   1.1       cgd 
    953   1.1       cgd /*
    954  1.17       tls  * Free a chunk, and possibly the page it's on, if the page becomes empty.
    955   1.1       cgd  */
    956  1.17       tls 
    957  1.17       tls static __inline__ void
    958  1.17       tls free_bytes(void *ptr, int index, struct pginfo *info)
    959  1.17       tls {
    960  1.17       tls     int i;
    961  1.17       tls     struct pginfo **mp;
    962  1.17       tls     void *vp;
    963  1.17       tls 
    964  1.17       tls     /* Find the chunk number on the page */
    965  1.17       tls     i = ((u_long)ptr & malloc_pagemask) >> info->shift;
    966  1.17       tls 
    967  1.17       tls     if (((u_long)ptr & (info->size-1))) {
    968  1.17       tls 	wrtwarning("modified (chunk-) pointer.\n");
    969  1.17       tls 	return;
    970  1.17       tls     }
    971  1.17       tls 
    972  1.17       tls     if (info->bits[i/MALLOC_BITS] & (1<<(i%MALLOC_BITS))) {
    973  1.17       tls 	wrtwarning("chunk is already free.\n");
    974  1.17       tls 	return;
    975  1.17       tls     }
    976  1.17       tls 
    977  1.17       tls     if (malloc_junk)
    978  1.17       tls 	memset(ptr, SOME_JUNK, info->size);
    979  1.17       tls 
    980  1.17       tls     info->bits[i/MALLOC_BITS] |= 1<<(i%MALLOC_BITS);
    981  1.17       tls     info->free++;
    982  1.17       tls 
    983  1.17       tls     mp = page_dir + info->shift;
    984  1.17       tls 
    985  1.17       tls     if (info->free == 1) {
    986  1.17       tls 
    987  1.17       tls 	/* Page became non-full */
    988  1.17       tls 
    989  1.17       tls 	mp = page_dir + info->shift;
    990  1.17       tls 	/* Insert in address order */
    991  1.17       tls 	while (*mp && (*mp)->next && (*mp)->next->page < info->page)
    992  1.17       tls 	    mp = &(*mp)->next;
    993  1.17       tls 	info->next = *mp;
    994  1.17       tls 	*mp = info;
    995  1.17       tls 	return;
    996  1.17       tls     }
    997  1.17       tls 
    998  1.17       tls     if (info->free != info->total)
    999  1.17       tls 	return;
   1000  1.17       tls 
   1001  1.17       tls     /* Find & remove this page in the queue */
   1002  1.17       tls     while (*mp != info) {
   1003  1.17       tls 	mp = &((*mp)->next);
   1004  1.19   thorpej #ifdef MALLOC_EXTRA_SANITY
   1005  1.17       tls 	if (!*mp)
   1006  1.17       tls 		wrterror("(ES): Not on queue\n");
   1007  1.19   thorpej #endif /* MALLOC_EXTRA_SANITY */
   1008  1.17       tls     }
   1009  1.17       tls     *mp = info->next;
   1010  1.17       tls 
   1011  1.17       tls     /* Free the page & the info structure if need be */
   1012  1.17       tls     page_dir[ptr2index(info->page)] = MALLOC_FIRST;
   1013  1.17       tls     vp = info->page;		/* Order is important ! */
   1014  1.17       tls     if(vp != (void*)info)
   1015  1.17       tls 	ifree(info);
   1016  1.17       tls     ifree(vp);
   1017  1.17       tls }
   1018  1.17       tls 
   1019  1.17       tls static void
   1020  1.17       tls ifree(void *ptr)
   1021  1.17       tls {
   1022  1.17       tls     struct pginfo *info;
   1023  1.17       tls     int index;
   1024  1.17       tls 
   1025  1.17       tls     /* This is legal */
   1026  1.17       tls     if (!ptr)
   1027  1.17       tls 	return;
   1028  1.17       tls 
   1029  1.17       tls     if (!malloc_started) {
   1030  1.17       tls 	wrtwarning("malloc() has never been called.\n");
   1031  1.17       tls 	return;
   1032  1.17       tls     }
   1033  1.17       tls 
   1034  1.17       tls     /* If we're already sinking, don't make matters any worse. */
   1035  1.17       tls     if (suicide)
   1036  1.17       tls 	return;
   1037  1.17       tls 
   1038  1.17       tls     index = ptr2index(ptr);
   1039  1.17       tls 
   1040  1.17       tls     if (index < malloc_pageshift) {
   1041  1.17       tls 	wrtwarning("junk pointer, too low to make sense.\n");
   1042  1.17       tls 	return;
   1043  1.17       tls     }
   1044  1.17       tls 
   1045  1.17       tls     if (index > last_index) {
   1046  1.17       tls 	wrtwarning("junk pointer, too high to make sense.\n");
   1047  1.17       tls 	return;
   1048  1.17       tls     }
   1049  1.17       tls 
   1050  1.17       tls     info = page_dir[index];
   1051  1.17       tls 
   1052  1.17       tls     if (info < MALLOC_MAGIC)
   1053  1.17       tls         free_pages(ptr, index, info);
   1054  1.17       tls     else
   1055  1.17       tls 	free_bytes(ptr, index, info);
   1056  1.17       tls     return;
   1057  1.17       tls }
   1058  1.17       tls 
   1059  1.17       tls /*
   1060  1.17       tls  * These are the public exported interface routines.
   1061  1.17       tls  */
   1062  1.17       tls 
   1063  1.17       tls 
   1064  1.17       tls void *
   1065  1.17       tls malloc(size_t size)
   1066  1.17       tls {
   1067  1.17       tls     register void *r;
   1068  1.17       tls 
   1069  1.17       tls     THREAD_LOCK();
   1070  1.17       tls     malloc_func = " in malloc():";
   1071  1.17       tls     if (malloc_active++) {
   1072  1.17       tls 	wrtwarning("recursive call.\n");
   1073  1.17       tls         malloc_active--;
   1074  1.17       tls 	return (0);
   1075  1.17       tls     }
   1076  1.17       tls     if (!malloc_started)
   1077  1.17       tls 	malloc_init();
   1078  1.17       tls     if (malloc_sysv && !size)
   1079  1.17       tls 	r = 0;
   1080  1.17       tls     else
   1081  1.17       tls 	r = imalloc(size);
   1082  1.17       tls     UTRACE(0, size, r);
   1083  1.17       tls     malloc_active--;
   1084  1.17       tls     THREAD_UNLOCK();
   1085  1.17       tls     if (malloc_xmalloc && !r)
   1086  1.17       tls 	wrterror("out of memory.\n");
   1087  1.17       tls     return (r);
   1088  1.17       tls }
   1089  1.17       tls 
   1090   1.9  christos void
   1091  1.17       tls free(void *ptr)
   1092   1.1       cgd {
   1093  1.17       tls     THREAD_LOCK();
   1094  1.17       tls     malloc_func = " in free():";
   1095  1.17       tls     if (malloc_active++) {
   1096  1.17       tls 	wrtwarning("recursive call.\n");
   1097  1.17       tls 	malloc_active--;
   1098  1.17       tls 	return;
   1099  1.17       tls     } else {
   1100  1.17       tls 	ifree(ptr);
   1101  1.17       tls 	UTRACE(ptr, 0, 0);
   1102  1.17       tls     }
   1103  1.17       tls     malloc_active--;
   1104  1.17       tls     THREAD_UNLOCK();
   1105  1.17       tls     return;
   1106  1.17       tls }
   1107  1.17       tls 
   1108  1.17       tls void *
   1109  1.17       tls realloc(void *ptr, size_t size)
   1110  1.17       tls {
   1111  1.17       tls     register void *r;
   1112  1.17       tls 
   1113  1.17       tls     THREAD_LOCK();
   1114  1.17       tls     malloc_func = " in realloc():";
   1115  1.17       tls     if (malloc_active++) {
   1116  1.17       tls 	wrtwarning("recursive call.\n");
   1117  1.17       tls         malloc_active--;
   1118  1.17       tls 	return (0);
   1119  1.17       tls     }
   1120  1.17       tls     if (ptr && !malloc_started) {
   1121  1.17       tls 	wrtwarning("malloc() has never been called.\n");
   1122  1.17       tls 	ptr = 0;
   1123  1.17       tls     }
   1124  1.17       tls     if (!malloc_started)
   1125  1.17       tls 	malloc_init();
   1126  1.17       tls     if (malloc_sysv && !size) {
   1127  1.17       tls 	ifree(ptr);
   1128  1.17       tls 	r = 0;
   1129  1.17       tls     } else if (!ptr) {
   1130  1.17       tls 	r = imalloc(size);
   1131  1.17       tls     } else {
   1132  1.17       tls         r = irealloc(ptr, size);
   1133  1.17       tls     }
   1134  1.17       tls     UTRACE(ptr, size, r);
   1135  1.17       tls     malloc_active--;
   1136  1.17       tls     THREAD_UNLOCK();
   1137  1.17       tls     if (malloc_xmalloc && !r)
   1138  1.17       tls 	wrterror("out of memory.\n");
   1139  1.17       tls     return (r);
   1140   1.1       cgd }
   1141