📄 mem.c
字号:
/* mem.c - memory management routines for qhull This is a standalone program. To initialize memory: qh_meminit (stderr); / qh_meminitbuffers (qh IStracing, qh_MEMalign, 7, qh_MEMbufsize,qh_MEMinitbuf); qh_memsize(sizeof(facetT)); qh_memsize(sizeof(facetT)); ... qh_memsetup(); To free up all memory buffers: qh_memfreeshort (&curlong, &totlong); uses Quickfit algorithm (freelists for commonly allocated sizes) assumes small sizes for freelists (it discards the tail of memory buffers) see README and mem.h see global.c (qh_initbuffers) for an example of using mem.c if qh_NOmem, malloc/free is used instead of mem.c copyright (c) 1993-1995 The Geometry Center*/#include <stdio.h>#include <stdlib.h>#include <string.h>#include "mem.h"#ifndef qhDEFqhullvoid qh_errexit(int exitcode, void *, void *);#endif/* ============ -global data structure ============== see mem.h for definition*/qhmemT qhmem= {0}; /* remove "= {0}" if this causes a compiler error */#ifndef qh_NOmem/* internal functions */ static int qh_intcompare(const void *i, const void *j);/*========== functions in alphabetical order ======== *//*--------------------------------------------------intcompare- used by qsort and bsearch to compare two integers*/static int qh_intcompare(const void *i, const void *j) { return(*((int *)i) - *((int *)j));} /* intcompare *//*--------------------------------------------------memalloc- allocates memory for object from qhmemreturns: pointer to allocated memory (errors if insufficient memory)notes: use qh_memalloc_() for inline code for quick allocations use explicit type conversion to avoid type warnings on some compilers*/void *qh_memalloc(int insize) { void **freelistp, *newbuffer; int index, size; int outsize, bufsize; void *object; if ((unsigned) insize <= (unsigned) qhmem.LASTsize) { index= qhmem.indextable[insize]; freelistp= qhmem.freelists+index; if ((object= *freelistp)) { qhmem.cntquick++; *freelistp= *((void **)*freelistp); /* replace freelist with next object */ return (object); }else { outsize= qhmem.sizetable[index]; qhmem.cntshort++; if (outsize > qhmem .freesize) { if (!qhmem.curbuffer) bufsize= qhmem.BUFinit; else bufsize= qhmem.BUFsize; qhmem.totshort += bufsize; if (!(newbuffer= malloc(bufsize))) { fprintf(qhmem.ferr, "qhull error (qh_memalloc): insufficient memory\n"); qh_errexit(qhmem_ERRmem, NULL, NULL); } *((void **)newbuffer)= qhmem.curbuffer; /* prepend newbuffer to curbuffer list */ qhmem.curbuffer= newbuffer; size= (sizeof(void **) + qhmem.ALIGNmask) & ~qhmem.ALIGNmask; qhmem.freemem= (void *)((char *)newbuffer+size); qhmem.freesize= bufsize - size; } object= qhmem.freemem; qhmem.freemem= (void *)((char *)qhmem.freemem + outsize); qhmem.freesize -= outsize; return object; } }else { /* long allocation */ if (!qhmem.indextable) { fprintf (qhmem.ferr, "qhull internal error (qh_memalloc): qhmem has not been initialized.\n"); qh_errexit(qhmem_ERRqhull, NULL, NULL); } outsize= insize; qhmem .cntlong++; qhmem .curlong++; qhmem .totlong += outsize; if (qhmem.maxlong < qhmem.totlong) qhmem.maxlong= qhmem.totlong; if (!(object= malloc(outsize))) { fprintf(qhmem.ferr, "qhull error (qh_memalloc): insufficient memory\n"); qh_errexit(qhmem_ERRmem, NULL, NULL); } if (qhmem.IStracing >= 5) fprintf (qhmem.ferr, "qh_memalloc long: %d bytes at %p\n", outsize, object); } return (object);} /* memalloc *//*--------------------------------------------------memfree- frees memory object (may be NULL) size is insize from qh_memalloc type checking warns if using (void **)object qh_memfree_()- in-line code for quick free's*/void qh_memfree(void *object, int size) { void **freelistp; if (!object) return; if (size <= qhmem.LASTsize) { qhmem .freeshort++; freelistp= qhmem.freelists + qhmem.indextable[size]; *((void **)object)= *freelistp; *freelistp= object; }else { qhmem .freelong++; qhmem .totlong -= size; free (object); if (qhmem.IStracing >= 5) fprintf (qhmem.ferr, "qh_memfree long: %d bytes at %p\n", size, object); }} /* memfree *//*--------------------------------------------------memfreeshort- frees up all short and qhmem memory allocationsreturns: number and size of current long allocations*/void qh_memfreeshort (int *curlong, int *totlong) { void *buffer, *nextbuffer; *curlong= qhmem .cntlong - qhmem .freelong; *totlong= qhmem .totlong; for(buffer= qhmem.curbuffer; buffer; buffer= nextbuffer) { nextbuffer= *((void **) buffer); free(buffer); } qhmem.curbuffer= NULL; if (qhmem .LASTsize) { free (qhmem .indextable); free (qhmem .freelists); free (qhmem .sizetable); } memset((char *)&qhmem, 0, sizeof qhmem); /* every field is 0, FALSE, NULL */} /* memfreeshort *//*--------------------------------------------------meminit- initialize memory (memalloc errors until memsetup)*/void qh_meminit (FILE *ferr) { memset((char *)&qhmem, 0, sizeof qhmem); /* every field is 0, FALSE, NULL */ qhmem.ferr= ferr; if (sizeof(void*) < sizeof(int)) { fprintf (ferr, "qhull internal error (qh_meminit): sizeof(void*) < sizeof(int). set.c will not work\n"); exit (1); /* can not use qh_errexit() */ }} /* meminit *//*--------------------------------------------------meminitbuffers- initialize memory buffers*/void qh_meminitbuffers (int tracelevel, int alignment, int numsizes, int bufsize, int bufinit) { qhmem.IStracing= tracelevel; qhmem.NUMsizes= numsizes; qhmem.BUFsize= bufsize; qhmem.BUFinit= bufinit; qhmem.ALIGNmask= alignment-1; if (qhmem.ALIGNmask & ~qhmem.ALIGNmask) { fprintf (qhmem.ferr, "qhull internal error (qh_meminit): memory alignment %d is not a power of 2\n", alignment); qh_errexit (qhmem_ERRqhull, NULL, NULL); } qhmem.sizetable= (int *) calloc (numsizes, sizeof(int)); qhmem.freelists= (void **) calloc (numsizes, sizeof(void *)); if (!qhmem.sizetable || !qhmem.freelists) { fprintf(qhmem.ferr, "qhull error (qh_meminit): insufficient memory\n"); qh_errexit (qhmem_ERRmem, NULL, NULL); } if (qhmem.IStracing >= 1) fprintf (qhmem.ferr, "qh_meminitbuffers: memory initialized with alignment %d\n", alignment);} /* meminitbuffers *//*--------------------------------------------------memsetup- set up memory after running memsize()*/void qh_memsetup (void) { int k,i; qsort(qhmem.sizetable, qhmem.TABLEsize, sizeof(int), qh_intcompare); qhmem.LASTsize= qhmem.sizetable[qhmem.TABLEsize-1]; if (qhmem .LASTsize >= qhmem .BUFsize || qhmem.LASTsize >= qhmem .BUFinit) { fprintf (qhmem.ferr, "qhull error (qh_memsetup): largest mem size %d is >= buffer size %d or initial buffer size %d\n", qhmem .LASTsize, qhmem .BUFsize, qhmem .BUFinit); qh_errexit(qhmem_ERRmem, NULL, NULL); } if (!(qhmem.indextable= (int *)malloc((qhmem.LASTsize+1) * sizeof(int)))) { fprintf(qhmem.ferr, "qhull error (qh_memsetup): insufficient memory\n"); qh_errexit(qhmem_ERRmem, NULL, NULL); } for(k=qhmem.LASTsize+1; k--; ) qhmem.indextable[k]= k; i= 0; for(k= 0; k <= qhmem.LASTsize; k++) { if (qhmem.indextable[k] <= qhmem.sizetable[i]) qhmem.indextable[k]= i; else qhmem.indextable[k]= ++i; }} /* memsetup *//*--------------------------------------------------memsize- define a free list for this size*/void qh_memsize(int size) { int k; if (qhmem .LASTsize) { fprintf (qhmem .ferr, "qhull error (qh_memsize): called after qhmem_setup\n"); qh_errexit (qhmem_ERRqhull, NULL, NULL); } size= (size + qhmem.ALIGNmask) & ~qhmem.ALIGNmask; for(k= qhmem.TABLEsize; k--; ) { if (qhmem.sizetable[k] == size) return; } if (qhmem.TABLEsize < qhmem.NUMsizes) qhmem.sizetable[qhmem.TABLEsize++]= size; else fprintf(qhmem.ferr, "qhull warning (memsize): free list table has room for only %d sizes\n", qhmem.NUMsizes);} /* memsize *//*--------------------------------------------------memstatistics- print out memory statistics does not account for wasted memory at the end of each block*/void qh_memstatistics (FILE *fp) { int i, count, totfree= 0; void *object; for (i=0; i<qhmem.TABLEsize; i++) { count=0; for (object= qhmem .freelists[i]; object; object= *((void **)object)) count++; totfree += qhmem.sizetable[i] * count; } fprintf (fp, "\nmemory statistics:\n\%7d quick allocations\n\%7d short allocations\n\%7d long allocations\n\%7d short frees\n\%7d long frees\n\%7d bytes of short memory in use\n\%7d bytes of short memory in freelists\n\%7d bytes of long memory allocated (except for input)\n\%7d bytes of long memory in use (in %d pieces)\n\%7d bytes per memory buffer (initially %d bytes)\n", qhmem .cntquick, qhmem.cntshort, qhmem.cntlong, qhmem .freeshort, qhmem.freelong, qhmem .totshort - qhmem .freesize - totfree, totfree, qhmem .maxlong, qhmem .totlong, qhmem .cntlong - qhmem .freelong, qhmem .BUFsize, qhmem .BUFinit); if (qhmem.cntlarger) { fprintf (fp, "%7d calls to qh_setlarger\n%7.2g average copy size\n", qhmem.cntlarger, ((float) qhmem.totlarger)/ qhmem.cntlarger); fprintf (fp, " freelists (bytes->count):"); } for (i=0; i<qhmem.TABLEsize; i++) { count=0; for (object= qhmem .freelists[i]; object; object= *((void **)object)) count++; fprintf (fp, " %d->%d", qhmem.sizetable[i], count); } fprintf (fp, "\n\n");} /* memstatistics */#else /* qh_NOmem, use malloc/free instead */void *qh_memalloc(int insize) { void *object; if (!(object= malloc(insize))) { fprintf(qhmem.ferr, "qhull error (qh_memalloc): insufficient memory\n"); qh_errexit(qhmem_ERRmem, NULL, NULL); } if (qhmem.IStracing >= 5) fprintf (qhmem.ferr, "qh_memalloc long: %d bytes at %p\n", insize, object); return object;}void qh_memfree(void *object, int size) { if (!object) return; free (object); if (qhmem.IStracing >= 5) fprintf (qhmem.ferr, "qh_memfree long: %d bytes at %p\n", size, object);}void qh_memfreeshort (int *curlong, int *totlong) { memset((char *)&qhmem, 0, sizeof qhmem); /* every field is 0, FALSE, NULL */ *curlong= 0; *totlong= 0;}void qh_meminit (FILE *ferr) { memset((char *)&qhmem, 0, sizeof qhmem); /* every field is 0, FALSE, NULL */ qhmem.ferr= ferr; if (sizeof(void*) < sizeof(int)) { fprintf (ferr, "qhull internal error (qh_meminit): sizeof(void*) < sizeof(int). set.c will not work\n"); qh_errexit (qhmem_ERRqhull, NULL, NULL); }}void qh_meminitbuffers (int tracelevel, int alignment, int numsizes, int bufsize, int bufinit) { qhmem.IStracing= tracelevel;}void qh_memsetup (void) {}void qh_memsize(int size) {}void qh_memstatistics (FILE *fp) {}#endif /* qh_NOmem */
⌨️ 快捷键说明
复制代码
Ctrl + C
搜索代码
Ctrl + F
全屏模式
F11
切换主题
Ctrl + Shift + D
显示快捷键
?
增大字号
Ctrl + =
减小字号
Ctrl + -