X-Git-Url: https://git.distorted.org.uk/u/mdw/catacomb/blobdiff_plain/d3409d5ecf2492cff862616de72a580d1a8e8dc0..2685767a6125c1620719c7de6234aedf41857b7e:/mparena.c diff --git a/mparena.c b/mparena.c index 4e02454..95f88d5 100644 --- a/mparena.c +++ b/mparena.c @@ -1,6 +1,6 @@ /* -*-c-*- * - * $Id: mparena.c,v 1.1 1999/11/17 18:02:16 mdw Exp $ + * $Id: mparena.c,v 1.5 2000/06/17 11:35:48 mdw Exp $ * * Allocation and freeing of MP buffers * @@ -30,6 +30,18 @@ /*----- Revision history --------------------------------------------------* * * $Log: mparena.c,v $ + * Revision 1.5 2000/06/17 11:35:48 mdw + * Overhaul to use mLib's arena system underneath. + * + * Revision 1.4 1999/12/10 23:28:52 mdw + * Memory allocation counting. + * + * Revision 1.3 1999/11/22 13:58:00 mdw + * Document the tweakables. + * + * Revision 1.2 1999/11/21 22:14:19 mdw + * Fix bug. Improve diagnostic capabilities. + * * Revision 1.1 1999/11/17 18:02:16 mdw * New multiprecision integer arithmetic suite. * @@ -41,26 +53,51 @@ #include #include -#include +#include +#include #include #include "mparena.h" -/*----- Default allocator -------------------------------------------------*/ +/*----- Tweakables --------------------------------------------------------*/ -static void *defalloc(mparena *a, size_t sz) { return xmalloc(sz); } -static void deffree(mparena *a, void *p) { free(p); } +/* --- @MPARENA_TRIVIAL@ --- * + * + * Make the allocator a passthrough. It immediately calls the underlying + * allocation functions rather than attempting to keep track of blocks + * itself. + */ -mparena_ops mparena_defops = { defalloc, deffree }; +/* #define MPARENA_TRIVIAL */ + +/* --- @MPARENA_DEBUG@ --- * + * + * The name of an output trace file to which logging information about the + * state of arena trees should be written. If unset, no logging is done. + */ + +/* #define MPARENA_DEBUG "mparena.out" */ /*----- Static variables --------------------------------------------------*/ -static mparena arena = { 0, &mparena_defops }; +#ifdef MPARENA_DEBUG + static FILE *debugfp = 0; + +# define MPARENA_OPENFILE do { \ + if (!debugfp) { \ + if ((debugfp = fopen(MPARENA_DEBUG, "w")) == 0) { \ + fprintf(stderr, "couldn't open debug output file\n"); \ + exit(EXIT_FAILURE); \ + } \ + } \ + } while (0) + +#endif + +/*----- Standard arenas ---------------------------------------------------*/ -#define MPARENA_RESOLVE(a) do { \ - if ((a) == MPARENA_GLOBAL) \ - (a) = &arena; \ -} while (0) +mparena mparena_global = MPARENA_INIT; +mparena mparena_secure = MPARENA_INIT; /*----- Main code ---------------------------------------------------------*/ @@ -73,19 +110,23 @@ static mparena arena = { 0, &mparena_defops }; * Use: Recursively dumps out the allocation tree. */ +#ifdef MPARENA_DEBUG + static void tdump(mparena_node *n) { if (!n) - putchar('*'); + putc('*', debugfp); else { - putchar('('); + putc('(', debugfp); tdump(n->left); - printf(", %u, ", n->v[0]); + fprintf(debugfp, ", %u, ", n->v[0]); tdump(n->right); - putchar(')'); + putc(')', debugfp); } } +#endif + /* --- @mparena_create@ --- * * * Arguments: @mparena *a@ = pointer to arena block @@ -99,28 +140,21 @@ static void tdump(mparena_node *n) void mparena_create(mparena *a) { a->root = 0; - a->ops = &mparena_defops; + a->n = 0; + a->a = &arena_stdlib; } -/* --- @mparena_setops@ --- * +/* --- @mparena_setarena@ --- * * - * Arguments: @mparena *a@ = pointer to arena block - * @mparena_ops *ops@ = pointer to operations block or null + * Arguments: @mparena *a@ = pointer to MP arena block + * @arena *aa@ = pointer to arena * - * Returns: The previous operations block. + * Returns: --- * - * Use: Sets or queries the operations attached to an arena. + * Use: Sets the underlying arena for an MP arena. */ -mparena_ops *mparena_setops(mparena *a, mparena_ops *ops) -{ - mparena_ops *o; - MPARENA_RESOLVE(a); - o = a->ops; - if (ops) - a->ops = ops; - return (0); -} +extern void mparena_setarena(mparena *a, arena *aa) { a->a = aa; } /* --- @mparena_destroy@ --- * * @@ -135,7 +169,7 @@ mparena_ops *mparena_setops(mparena *a, mparena_ops *ops) static void tfree(mparena *a, mparena_node *n) { - a->ops->free(a, n->v); + A_FREE(a->a, n->v); if (n->left) tfree(a, n->left); if (n->right) @@ -149,6 +183,21 @@ void mparena_destroy(mparena *a) a->root = 0; } +/* --- @mparena_count@ --- * + * + * Arguments: @mparena *a@ = pointer to arena block + * + * Returns: Number of allocated blocks from this arena. + * + * Use: Reports the number of blocks allocated from the arena and not + * yet freed. + */ + +unsigned mparena_count(mparena *a) +{ + return (a->n); +} + /* --- @mpalloc@ --- * * * Arguments: @mparena *a@ = pointer to arena block @@ -160,17 +209,30 @@ void mparena_destroy(mparena *a) * digits. */ +#ifdef MPARENA_TRIVIAL + +mpw *mpalloc(mparena *a, size_t sz) +{ + mpw *v; + v = A_ALLOC(a->a, MPWS(sz)); + if (!v) + THROW(EXC_NOMEM); + return (v); +} + +#else + mpw *mpalloc(mparena *a, size_t sz) { mparena_node **nn, *n; mpw *v; - MPARENA_RESOLVE(a); nn = &a->root; -#ifdef notdef - printf("*** alloc %u\n", sz); - tdump(a->root); putchar('\n'); +#ifdef MPARENA_DEBUG + MPARENA_OPENFILE; + fprintf(debugfp, "alloc %u\n before: ", sz); + tdump(a->root); putc('\n', debugfp); #endif /* --- First, find a block which is big enough --- */ @@ -178,8 +240,13 @@ mpw *mpalloc(mparena *a, size_t sz) again: n = *nn; if (!n) { - v = a->ops->alloc(a, MPWS(sz + 1)); +#ifdef MPARENA_DEBUG + fputs(" failed\n", debugfp); +#endif + if ((v = A_ALLOC(a->a, MPWS(sz + 1))) == 0) + THROW(EXC_NOMEM); v[0] = sz; + a->n++; return (v + 1); } if (n->v[0] < sz) { @@ -196,7 +263,7 @@ again: /* --- If the block we've got is still too large, start digging --- */ - if (n->v[0] >= sz * 2) { + if (n->v[0] > sz * 2) { nn = &n->left; goto again; } @@ -219,12 +286,20 @@ again: p->left = left; } +#ifdef MPARENA_DEBUG + fputs(" after: ", debugfp); + tdump(a->root); putc('\n', debugfp); +#endif + /* --- Get rid of this node now --- */ DESTROY(n); + a->n++; return (v + 1); } +#endif + /* --- @mpfree@ --- * * * Arguments: @mparena *a@ = pointer to arena block @@ -232,18 +307,30 @@ again: * * Returns: --- * - * Use: Returns an MP vector to an arena. It doesn't have to be - * returned to the arena from which it was allocated. + * Use: Returns an MP vector to an arena. */ +#ifdef MPARENA_TRIVIAL + +void mpfree(mparena *a, mpw *v) +{ + A_FREE(a->a, v); +} + +#else + void mpfree(mparena *a, mpw *v) { mparena_node **nn, *n; size_t sz = *--v; - MPARENA_RESOLVE(a); - nn = &a->root; +#ifdef MPARENA_DEBUG + MPARENA_OPENFILE; + fprintf(debugfp, "free %u\n before: ", sz); + tdump(a->root); putc('\n', debugfp); +#endif + nn = &a->root; while (*nn) { n = *nn; if (n->v[0] > sz) @@ -256,11 +343,14 @@ void mpfree(mparena *a, mpw *v) n->left = n->right = 0; n->v = v; *nn = n; + a->n--; -#ifdef notdef - printf("*** free %u\n", sz); - tdump(a->root); putchar('\n'); +#ifdef MPARENA_DEBUG + fputs(" after: ", debugfp); + tdump(a->root); putc('\n', debugfp); #endif } +#endif + /*----- That's all, folks -------------------------------------------------*/