pygr/cgraph.c

   1
   2
   3 #include "cgraph.h"
   4
   5
   6 CDict *cdict_alloc(int n)
   7 {
   8   CDict *d=0;
   9
  10   d=calloc(1,sizeof(CDict));
  11   if (d==0) /* calloc FAILED!! */
  12     return 0;
  13   d->dict=calloc(n,sizeof(CDictEntry));
  14   if (d->dict==0) { /* calloc FAILED!! */
  15     free(d); /* DUMP OUR EMPTY STRUCTURE */
  16     return 0;
  17   }
  18   return d; /* RETURN OUR DATA STRUCTURE */
  19 }
  20
  21
  22 int cdict_free(CDict *d)
  23 {
  24   free(d->dict);
  25   free(d);
  26   return 0;
  27 }
  28
  29
  30 int cdict_qsort_cmp(const void *void_a,const void *void_b)
  31 { /* STRAIGHTFORWARD COMPARISON OF SIGNED start VALUES, LONGER INTERVALS 1ST */
  32   CDictEntry *a=(CDictEntry *)void_a,*b=(CDictEntry *)void_b;
  33   if (a->k<b->k)
  34     return -1;
  35   else if (a->k>b->k)
  36     return 1;
  37   else
  38     return 0;
  39 }
  40
  41
  42 CDictEntry *cdict_getitem(CDict *d,int k)
  43 {
  44   int l=0,mid,r;
  45   CDictEntry *p;
  46
  47   if (d==0) /* HANDLE NULL POINTER PROPERLY */
  48     return 0;
  49
  50   p=d->dict; /* SORTED ARRAY OF ENTRIES */
  51   r=d->n;
  52   while (l<r) {
  53     mid=(l+r)/2;
  54     if (p[mid].k==k)
  55       return p+mid;
  56     else if (p[mid].k<k)
  57       l=mid+1;
  58     else
  59       r=mid;
  60   }
  61   return 0;
  62 }
  63
  64
  65
  66 CGraph *cgraph_alloc(int n)
  67 {
  68   CGraph *d=0;
  69
  70   d=calloc(1,sizeof(CGraph));
  71   if (d==0) /* calloc FAILED!! */
  72     return 0;
  73   d->dict=calloc(n,sizeof(CGraphEntry));
  74   if (d->dict==0) { /* calloc FAILED!! */
  75     free(d); /* DUMP OUR EMPTY STRUCTURE */
  76     return 0;
  77   }
  78   return d; /* RETURN OUR DATA STRUCTURE */
  79 }
  80
  81
  82 int cgraph_free(CGraph *d)
  83 {
  84   int i;
  85   for (i=0;i<d->n;i++) /* DUMP ALL ASSOCIATED DICTIONARIES */
  86     cdict_free(d->dict[i].v);
  87   free(d->dict);
  88   free(d);
  89   return 0;
  90 }
  91
  92
  93 CGraphEntry *cgraph_getitem(CGraph *d,int k)
  94 {
  95   int l=0,mid,r;
  96   CGraphEntry *p;
  97
  98   if (d==0) /* HANDLE NULL POINTER PROPERLY */
  99     return 0;
 100
 101   p=d->dict; /* SORTED ARRAY OF ENTRIES */
 102   r=d->n;
 103   while (l<r) {
 104     mid=(l+r)/2;
 105     if (p[mid].k==k)
 106       return p+mid;
 107     else if (p[mid].k<k)
 108       l=mid+1;
 109     else
 110       r=mid;
 111   }
 112   return 0;
 113 }
 114
 115
 116 int *calloc_int(int n)
 117 {
 118   return (int *)calloc(n,sizeof(int));
 119 }