4.4BSD/usr/src/contrib/news/inn/innd/ng.c
/* $Revision: 1.19 $
**
** Routine for the in-core data structures for the active and newsfeeds
** files.
*/
#include "innd.h"
#include "mydir.h"
/*
** Hash function taken from Chris Torek's hash package posted to
** comp.lang.c on 18-Oct-90 in <27038@mimsy.umd.edu>. Thanks, Chris.
*/
#define NGH_HASH(Name, p, j) \
for (p = Name, j = 0; *p; ) j = (j << 5) + j + *p++
/*
** Size of hash table. Change NGH_BUCKET if not a power of two.
*/
#define NGH_SIZE 512
#define NGH_BUCKET(j) &NGHtable[j & (NGH_SIZE - 1)]
/*
** Newsgroup hash entry, which is really a hash bucket -- pointers
** to all the groups with this hash code.
*/
typedef struct _NGHASH {
int Size;
int Used;
NEWSGROUP **Groups;
} NGHASH;
STATIC BUFFER NGdirs;
STATIC BUFFER NGnames;
STATIC NGHASH NGHtable[NGH_SIZE];
STATIC int NGHbuckets;
STATIC int NGHcount;
/*
** Sorting predicate for qsort call in NGparsefile. Put newsgroups in
** rough order of their activity. Will be better if we write a "counts"
** file sometime.
*/
STATIC int
NGcompare(p1, p2)
POINTER p1;
POINTER p2;
{
NEWSGROUP **ng1;
NEWSGROUP **ng2;
ng1 = CAST(NEWSGROUP**, p1);
ng2 = CAST(NEWSGROUP**, p2);
return ng1[0]->Last - ng2[0]->Last;
}
/*
** Convert a newsgroup name into a directory name.
*/
STATIC void
NGdirname(p)
register char *p;
{
for ( ; *p; p++)
if (*p == '.')
*p = '/';
}
/*
** Parse a single line from the active file, filling in ngp. Be careful
** not to write NUL's into the in-core copy, since we're either mmap(2)'d,
** or we want to just blat it out to disk later.
*/
STATIC BOOL
NGparseentry(ngp, p, end)
register NEWSGROUP *ngp;
register char *p;
register char *end;
{
register char *q;
register unsigned int j;
register NGHASH *htp;
register NEWSGROUP **ngpp;
register int i;
if ((q = strchr(p, ' ')) == NULL)
return FALSE;
i = q - p;
ngp->NameLength = i;
ngp->Name = &NGnames.Data[NGnames.Used];
(void)strncpy(ngp->Name, p, (SIZE_T)i);
ngp->Name[i] = '\0';
NGnames.Used += i + 1;
ngp->Dir = &NGdirs.Data[NGdirs.Used];
(void)strncpy(ngp->Dir, p, (SIZE_T)i);
ngp->Dir[i] = '\0';
NGdirs.Used += i + 1;
NGdirname(ngp->Dir);
ngp->LastString = ++q;
if ((q = strchr(q, ' ')) == NULL || q > end)
return FALSE;
ngp->Lastwidth = q - ngp->LastString;
if ((q = strchr(q, ' ')) == NULL || q > end)
return FALSE;
if ((q = strchr(q + 1, ' ')) == NULL || q > end)
return FALSE;
ngp->Rest = ++q;
/* We count on atoi() to stop at the space after the digits! */
ngp->Last = atol(ngp->LastString);
ngp->nSites = 0;
ngp->Sites = NEW(int, NGHcount);
ngp->Alias = NULL;
/* Find the right bucket for the group, make sure there is room. */
/* SUPPRESS 6 *//* Over/underflow from plus expression */
NGH_HASH(ngp->Name, p, j);
htp = NGH_BUCKET(j);
for (p = ngp->Name, ngpp = htp->Groups, i = htp->Used; --i >= 0; ngpp++)
if (*p == ngpp[0]->Name[0] && EQ(p, ngpp[0]->Name)) {
syslog(L_ERROR, "%s duplicate_group %s", LogName, p);
return FALSE;
}
if (htp->Used >= htp->Size) {
htp->Size += NGHbuckets;
RENEW(htp->Groups, NEWSGROUP*, htp->Size);
}
htp->Groups[htp->Used++] = ngp;
return TRUE;
}
/*
** Parse the active file, building the initial Groups global.
*/
void
NGparsefile()
{
register char *p;
register char *q;
register int i;
register BOOL SawMe;
register NEWSGROUP *ngp;
register NGHASH *htp;
char **strings;
char *active;
char *end;
/* If re-reading, remove anything we might have had. */
if (Groups) {
for (i = nGroups, ngp = Groups; --i >= 0; ngp++)
DISPOSE(ngp->Sites);
DISPOSE(Groups);
DISPOSE(GroupPointers);
DISPOSE(NGdirs.Data);
DISPOSE(NGnames.Data);
}
/* Get active file and space for group entries. */
active = ICDreadactive(&end);
for (p = active, i = 0; p < end && (p = strchr(p, '\n')) != NULL; p++, i++)
continue;
nGroups = i;
Groups = NEW(NEWSGROUP, nGroups);
GroupPointers = NEW(NEWSGROUP*, nGroups);
/* Get space to hold copies of the names and the directory names.
* This might take more space than individually allocating each
* element, but it is definitely easier on the system. */
i = end - active;
NGdirs.Size = i;
NGdirs.Data = NEW(char, NGdirs.Size + 1);
NGdirs.Used = 0;
NGnames.Size = i;
NGnames.Data = NEW(char, NGnames.Size + 1);
NGnames.Used = 0;
/* Set up the default hash buckets. */
NGHbuckets = nGroups / NGH_SIZE;
if (NGHbuckets == 0)
NGHbuckets = 1;
if (NGHtable[0].Groups)
for (i = NGH_SIZE, htp = NGHtable; --i >= 0; htp++)
htp->Used = 0;
else
for (i = NGH_SIZE, htp = NGHtable; --i >= 0; htp++) {
htp->Size = NGHbuckets;
htp->Groups = NEW(NEWSGROUP*, htp->Size);
htp->Used = 0;
}
/* Count the number of sites. */
SawMe = FALSE;
for (strings = SITEreadfile(TRUE), i = 0; (p = strings[i]) != NULL; i++)
if (*p == 'M' && *++p == 'E' && *++p == ':')
SawMe = TRUE;
if (i == 0 || (i == 1 && SawMe)) {
syslog(L_ERROR, "%s bad_newsfeeds no feeding sites", LogName);
NGHcount = 1;
}
else
NGHcount = i;
/* Loop over all lines in the active file, filling in the fields of
* the Groups array. */
for (p = active, ngp = Groups, i = nGroups; --i >= 0; ngp++, p = q + 1) {
ngp->Start = p - active;
if ((q = strchr(p, '\n')) == NULL || !NGparseentry(ngp, p, q)) {
syslog(L_FATAL, "%s bad_active %s...", LogName, MaxLength(p, p));
exit(1);
}
}
/* Sort each bucket. */
for (i = NGH_SIZE, htp = NGHtable; --i >= 0; htp++)
if (htp->Used > 1)
qsort((POINTER)htp->Groups, (SIZE_T)htp->Used,
sizeof htp->Groups[0], NGcompare);
/* Chase down any alias flags. */
for (ngp = Groups, i = nGroups; --i >= 0; ngp++)
if (ngp->Rest[0] == NF_FLAG_ALIAS) {
ngp->Alias = ngp;
if ((p = strchr(ngp->Alias->Rest, '\n')) != NULL)
*p = '\0';
ngp->Alias = NGfind(&ngp->Alias->Rest[1]);
if (p)
*p = '\n';
if (ngp->Alias != NULL && ngp->Alias->Rest[0] == NF_FLAG_ALIAS)
syslog(L_NOTICE, "%s alias_error %s too many levels",
LogName, ngp->Name);
}
}
/*
** Hash a newsgroup and see if we get it.
*/
NEWSGROUP *
NGfind(Name)
char *Name;
{
register char *p;
register int i;
register unsigned int j;
register NEWSGROUP **ngp;
char c;
NGHASH *htp;
/* SUPPRESS 6 *//* Over/underflow from plus expression */
NGH_HASH(Name, p, j);
htp = NGH_BUCKET(j);
for (c = *Name, ngp = htp->Groups, i = htp->Used; --i >= 0; ngp++)
if (c == ngp[0]->Name[0] && EQ(Name, ngp[0]->Name))
return ngp[0];
return NULL;
}
/*
** Split a newsgroups header line into the groups we get. Return a
** point to static memory and clobber the argument along the way.
*/
char **
NGsplit(p)
register char *p;
{
static char **groups;
static int oldlength;
register char **gp;
register int i;
/* Get an array of character pointers. */
i = strlen(p);
if (groups == NULL) {
groups = NEW(char*, i + 1);
oldlength = i;
}
else if (oldlength < i) {
RENEW(groups, char*, i + 1);
oldlength = i;
}
/* Loop over text. */
for (gp = groups; *p; *p++ = '\0') {
/* Skip leading separators. */
for (; NG_ISSEP(*p); p++)
continue;
if (*p == '\0')
break;
/* Mark the start of the newsgroup, move to the end of it. */
for (*gp++ = p; *p && !NG_ISSEP(*p); p++)
continue;
if (*p == '\0')
break;
}
*gp = NULL;
return groups;
}
/*
** Renumber a group.
*/
BOOL
NGrenumber(ngp)
NEWSGROUP *ngp;
{
static char NORENUMBER[] = "%s cant renumber %s %s too wide";
static char RENUMBER[] = "%s renumber %s %s from %ld to %ld";
register DIR *dp;
register DIRENTRY *ep;
register char *f2;
register char *p;
char *f3;
char *f4;
char *start;
long l;
long himark;
long lomark;
char *dummy;
/* Get a valid offset into the active file. */
if (ICDneedsetup) {
syslog(L_ERROR, "%s unsynched must reload before renumber", LogName);
return FALSE;
}
start = ICDreadactive(&dummy) + ngp->Start;
/* Check the file format. */
if ((f2 = strchr(start, ' ')) == NULL
|| (f3 = strchr(++f2, ' ')) == NULL
|| (f4 = strchr(++f3, ' ')) == NULL) {
syslog(L_ERROR, "%s bad_format active %s",
LogName, MaxLength(start, start));
return FALSE;
}
himark = atol(f2);
lomark = himark + 1;
/* Scan the directory. */
if ((dp = opendir(ngp->Dir)) != NULL) {
while ((ep = readdir(dp)) != NULL) {
p = ep->d_name;
if (!CTYPE(isdigit, p[0]) || strspn(p, "0123456789") != strlen(p)
|| (l = atol(p)) == 0)
continue;
if (l < lomark)
lomark = l;
if (l > himark)
himark = l;
}
(void)closedir(dp);
}
l = atol(f2);
if (himark != l) {
syslog(L_NOTICE, RENUMBER, LogName, ngp->Name, "hi", l, himark);
if (!FormatLong(f2, himark, f3 - f2 - 1)) {
syslog(L_NOTICE, NORENUMBER, LogName, ngp->Name, "hi");
return FALSE;
}
ngp->Last = himark;
ICDactivedirty++;
}
l = atol(f3);
if (lomark != l) {
if (lomark < l)
syslog(L_NOTICE, RENUMBER, LogName, ngp->Name, "lo", l, lomark);
if (!FormatLong(f3, lomark, f4 - f3)) {
syslog(L_NOTICE, NORENUMBER, LogName, ngp->Name, "lo");
return FALSE;
}
ICDactivedirty++;
}
return TRUE;
}