2.11BSD#431 - /usr/src/new/nntp/server/active.c

   1: #ifndef lint
   2: static char *sccsid = "@(#)active.c	1.12	(Berkeley) 1/11/88";
   3: #endif
   4: 
   5: #include "common.h"
   6: 
   7: /*
   8:  * Routines to deal with the active file
   9:  */
  10: 
  11: int act_cmp();
  12: 
  13: /*
  14:  * read_groups -- read the active file into memory, sort it,
  15:  *	and return the number of newsgroups read in.
  16:  *	If FASTFORK is true, this can be called by interrupt,
  17:  *	and may have to free up the old storage.  We decide
  18:  *	this by the fact that "num_groups" will be non-zero if
  19:  *	we're here on an interrupt.
  20:  *
  21:  *	Parameters:	None.
  22:  *
  23:  *	Returns:	Number of newsgroups read into
  24:  *			memory.
  25:  *			Zero on error.
  26:  *
  27:  *	Side effects:	Reads newsgroups into "group_array"
  28:  *			and sorts them.
  29:  */
  30: 
  31: read_groups()
  32: {
  33:     register int    i;
  34:     register int    act_fd;
  35:     register char   *actbuf, *cp, *end;
  36:     char        *malloc();
  37:     struct stat statbuf;
  38: 
  39:     /*
  40: 	 * If we're here on an interrupt, free up all the
  41: 	 * previous groups.
  42: 	 */
  43: 
  44:     if (num_groups != 0) {
  45:         (void) free(group_array[0]);    /* Assume [0] -> actbuf */
  46:         (void) free(group_array);
  47:     }
  48: 
  49:     act_fd = open(activefile, O_RDONLY);
  50:     if (act_fd < 0) {
  51: #ifdef SYSLOG
  52:         syslog(LOG_ERR, "read_groups: open %s: %m", activefile);
  53: #endif
  54:         return (0);
  55:     }
  56: 
  57:     if (fstat(act_fd, &statbuf) < 0) {
  58: #ifdef SYSLOG
  59:         syslog(LOG_ERR, "read_groups: fstat: %m");
  60: #endif
  61:         (void) close(act_fd);
  62:         return (0);
  63:     }
  64: 
  65:     actbuf = malloc(statbuf.st_size);
  66:     if (actbuf == NULL) {
  67: #ifdef SYSLOG
  68:         syslog(LOG_ERR, "read_groups: malloc %d bytes: %m",
  69:             statbuf.st_size);
  70: #endif
  71:         (void) close(act_fd);
  72:         return (0);
  73:     }
  74: 
  75:     if (read(act_fd, actbuf, (int)statbuf.st_size) != statbuf.st_size) {
  76: #ifdef SYSLOG
  77:         syslog(LOG_ERR, "read_groups: read %d bytes: %m",
  78:             statbuf.st_size);
  79: #endif
  80:         (void) close(act_fd);
  81:         return (0);
  82:     }
  83: 
  84:     (void) close(act_fd);
  85: 
  86:     for (i = 0, cp = actbuf, end = actbuf + statbuf.st_size; cp < end; cp++)
  87:         if (*cp == '\n')
  88:             i++;
  89: 
  90:     group_array = (char **) malloc(i * (sizeof (char *)));
  91:     if (group_array == NULL) {
  92: #ifdef SYSLOG
  93:         syslog(LOG_ERR, "read_groups: malloc %d bytes: %m",
  94:             i * sizeof (char **));
  95: #endif
  96:         (void) close(act_fd);
  97:         return (0);
  98:     }
  99: 
 100:     cp = actbuf;
 101:     i = 0;
 102:     while (cp < end) {
 103:         group_array[i++] = cp;
 104:         cp = index(cp, '\n');
 105:         if (cp == NULL)
 106:             break;
 107:         *cp = '\0';
 108:         cp++;
 109:     }
 110: 
 111:     qsort((char *) group_array, i, sizeof (char *), act_cmp);
 112: 
 113:     return (i);
 114: }
 115: 
 116: 
 117: act_cmp(ptr1, ptr2)
 118:     char     **ptr1, **ptr2;
 119: {
 120:     return(strcmp(*ptr1, *ptr2));
 121: }
 122: 
 123: 
 124: /*
 125:  * find_group -- find a given newsgroup and return
 126:  *	the low and high message numbers in the group
 127:  *	(space provided by user).
 128:  *
 129:  *	Parameters:	"group" is the name of the group
 130:  *			we're searching for.
 131:  *			"num_groups" is the total number
 132:  *			of groups in the group array.
 133:  *			"low_msg" and "high_msg" are
 134:  *			pointers to where we're supposed
 135:  *			to put the low and high message numbers.
 136:  *
 137:  *	Returns:	0 if all goes well,
 138:  *			-1 if we can't find the group.
 139:  *
 140:  *	Side effects:	None.
 141:  */
 142: 
 143: find_group(group, num_groups, low_msg, high_msg)
 144:     char        *group;
 145:     int     num_groups;
 146:     int     *low_msg, *high_msg;
 147: {
 148:     char        kludgebuf[MAXBUFLEN];
 149:     int     cond;
 150:     register int    low, high, mid;
 151:     int     length;
 152: 
 153:     low = 0;
 154:     high = num_groups-1;
 155:     (void) strcpy(kludgebuf, group);
 156:     (void) strcat(kludgebuf, " ");
 157:     length = strlen(kludgebuf);
 158: 
 159:     while (low <= high) {
 160:         mid = (low + high) / 2;
 161:         if ((cond = strncmp(kludgebuf, group_array[mid], length)) < 0)
 162:             high = mid - 1;
 163:         else if (cond > 0)
 164:             low = mid + 1;
 165:         else {
 166:             (void) sscanf(group_array[mid], "%s %d %d",
 167:                 kludgebuf, high_msg, low_msg);
 168:             return(0);
 169:         }
 170:     }
 171:     return(-1);
 172: }

Defined functions

Defined variables