ref: 065c3557af8de1b20d94c2e86a4a29c5d33ccc67
dir: /sys/src/cmd/upas/fs/cache.c/
#include "common.h" #include <libsec.h> #include "dat.h" static void addlru(Mcache *c, Message *m) { Message *l, **ll; c->nlru++; ll = &c->lru; while((l = *ll) != nil){ if(l == m){ c->nlru--; *ll = m->lru; } else { ll = &l->lru; } } m->lru = nil; *ll = m; } static void notecache(Mailbox *mb, Message *m, long sz) { assert(Topmsg(mb, m)); assert(sz >= 0 && sz <= Maxmsg); m->csize += sz; mb->cached += sz; addlru(mb, m); } static void cachefree0(Mailbox *mb, Message *m, int force) { long sz, i; Message *s; if(!force && mb->fetch == nil) return; for(s = m->part; s; s = s->next) cachefree(mb, s, force); dprint("cachefree: %D %p, %p\n", m->fileid, m, m->start); if(m->mallocd){ free(m->start); m->mallocd = 0; } if(m->ballocd){ free(m->body); m->ballocd = 0; } if(m->hallocd){ free(m->header); m->hallocd = 0; } for(i = 0; i < nelem(m->references); i++){ free(m->references[i]); m->references[i] = 0; } sz = m->csize; m->csize = 0; m->start = 0; m->end = 0; m->header = 0; m->hend = 0; m->hlen = -1; m->body = 0; m->bend = 0; m->mheader = 0; m->mhend = 0; if(mb->decache) mb->decache(mb, m); m->decoded = 0; m->converted = 0; m->badchars = 0; m->cstate &= ~(Cheader|Cbody); if(Topmsg(mb, m)) mb->cached -= sz; } void cachefree(Mailbox *mb, Message *m, int force) { Message **ll; for(ll = &mb->lru; *ll != nil; ll = &((*ll)->lru)){ if(*ll == m){ mb->nlru--; *ll = m->lru; m->lru = nil; break; } } cachefree0(mb, m, force); } void putcache(Mailbox *mb, Message *m) { int n; while(!Topmsg(mb, m)) m = m->whole; addlru(mb, m); while(mb->lru != nil && (mb->cached > cachetarg || mb->nlru > 10)){ n = 0; while(mb->lru->refs > 0){ if(++n >= mb->nlru) return; addlru(mb, mb->lru); } cachefree(mb, mb->lru, 0); } } static int squeeze(Message *m, uvlong o, long l, int c) { char *p, *q, *e; int n; q = memchr(m->start + o, c, l); if(q == nil) return 0; n = 0; e = m->start + o + l; for(p = q; q < e; q++){ if(*q == c){ n++; continue; } *p++ = *q; } return n; } void msgrealloc(Message *m, ulong l) { long l0, h0, m0, me, b0; l0 = m->end - m->start; m->mallocd = 1; h0 = m->hend - m->start; m0 = m->mheader - m->start; me = m->mhend - m->start; b0 = m->body - m->start; assert(h0 >= 0 && m0 >= 0 && me >= 0 && b0 >= 0); m->start = erealloc(m->start, l + 1); m->rbody = m->start + b0; m->rbend = m->end = m->start + l0; if(!m->hallocd){ m->header = m->start; m->hend = m->start + h0; } if(!m->ballocd){ m->body = m->start + b0; m->bend = m->start + l0; } m->mheader = m->start + m0; m->mhend = m->start + me; } /* * the way we squeeze out bad characters is exceptionally sneaky. */ static int fetch(Mailbox *mb, Message *m, uvlong o, ulong l) { int expand; long l0, n, sz0; top: l0 = m->end - m->start; assert(l0 >= 0); dprint("fetch %lud sz %lud o %llud l %lud badchars %d\n", l0, m->size, o, l, m->badchars); if(l0 == m->size || o > m->size) return 0; expand = 0; if(o + l > m->size) l = m->size - o; if(o + l == m->size) l += m->ibadchars - m->badchars; if(o + l > l0){ expand = 1; msgrealloc(m, o + m->badchars + l); } assert(l0 <= o); sz0 = m->size; if(mb->fetch(mb, m, o + m->badchars, l) == -1){ logmsg(m, "can't fetch %D %llud %lud", m->fileid, o, l); m->deleted = Dead; return -1; } if(m->size - sz0) l += m->size - sz0; /* awful botch for gmail */ if(expand){ /* grumble. poor planning. */ if(m->badchars > 0) memmove(m->start + o, m->start + o + m->badchars, l); n = squeeze(m, o, l, 0); n += squeeze(m, o, l - n, '\r'); if(n > 0){ if(m->ibadchars == 0) dprint(" %ld more badchars\n", n); l -= n; m->badchars += n; msgrealloc(m, o + l); } notecache(mb, m, l); m->bend = m->rbend = m->end = m->start + o + l; if(n) if(o + l + n == m->size && m->cstate&Cidx){ dprint(" redux %llud %ld\n", o + l, n); o += l; l = n; goto top; } }else eprint("unhandled case in fetch\n"); *m->end = 0; return 0; } void cachehash(Mailbox *mb, Message *m) { if(m->whole == m->whole->whole) henter(PATH(mb->id, Qmbox), m->name, (Qid){PATH(m->id, Qdir), 0, QTDIR}, m, mb); else henter(PATH(m->whole->id, Qdir), m->name, (Qid){PATH(m->id, Qdir), 0, QTDIR}, m, mb); henter(PATH(m->id, Qdir), "xxx", (Qid){PATH(m->id, Qmax), 0, QTFILE}, m, mb); /* sleezy speedup */ } static char *itab[] = { "idx", "stale", "header", "body", "new", }; char* cstate(Message *m) { char *p, *e; int i, s; static char buf[64]; s = m->cstate; p = e = buf; e += sizeof buf; for(i = 0; i < 8; i++) if(s & 1<<i) if(i < nelem(itab)) p = seprint(p, e, "%s ", itab[i]); if(p > buf) p--; p[0] = 0; return buf; } static int middlecache(Mailbox *mb, Message *m) { int y; y = 0; while(!Topmsg(mb, m)){ m = m->whole; if((m->cstate & Cbody) == 0) y = 1; } if(y == 0) return 0; dprint("middlecache %d [%D] %lud %lud\n", m->id, m->fileid, (ulong)(m->end - m->start), m->size); return cachebody(mb, m); } int cacheheaders(Mailbox *mb, Message *m) { char *p, *e; int r; ulong o; if(!mb->fetch || m->cstate&Cheader) return 0; if(!Topmsg(mb, m)) return middlecache(mb, m); dprint("cacheheaders %d %D\n", m->id, m->fileid); if(m->size < 10000) r = fetch(mb, m, 0, m->size); else for(r = 0; (o = m->end - m->start) < m->size; ){ if((r = fetch(mb, m, o, 4096)) < 0) break; p = m->start + o; if(o) p--; for(e = m->end - 2; p < e; p++){ p = memchr(p, '\n', e - p); if(p == nil) break; if(p[1] == '\n' || (p[1] == '\r' && p[2] == '\n')) goto found; } } if(r < 0) return -1; found: parseheaders(mb, m, mb->addfrom, 0); return 0; } void digestmessage(Mailbox *mb, Message *m) { assert(m->digest == nil); m->digest = emalloc(SHA1dlen); sha1((uchar*)m->start, m->end - m->start, m->digest, nil); if(mtreeisdup(mb, m)){ logmsg(m, "dup detected"); m->deleted = Dup; /* no dups allowed */ }else mtreeadd(mb, m); dprint("%d %#A\n", m->id, m->digest); } int cachebody(Mailbox *mb, Message *m) { ulong o; while(!Topmsg(mb, m)) m = m->whole; if(!mb->fetch || m->cstate&Cbody) return 0; o = m->end - m->start; dprint("cachebody %d [%D] %lud %lud %s", m->id, m->fileid, o, m->size, cstate(m)); if(o < m->size) if(fetch(mb, m, o, m->size - o) < 0) return -1; if((m->cstate&Cidx) == 0){ assert(m->ibadchars == 0); if(m->badchars > 0) dprint("reducing size %ld %ld\n", m->size, m->size - m->badchars); m->size -= m->badchars; /* sneaky */ m->ibadchars = m->badchars; } if(m->digest == nil) digestmessage(mb, m); if(m->lines == 0) m->lines = countlines(m); parse(mb, m, mb->addfrom, 0); dprint(" →%s\n", cstate(m)); return 0; } int cacheidx(Mailbox *mb, Message *m) { if(m->cstate & Cidx) return 0; if(cachebody(mb, m) == -1) return -1; m->cstate |= Cidxstale|Cidx; return 0; } static int countparts(Message *m) { Message *p; if(m->nparts == 0) for(p = m->part; p; p = p->next){ countparts(p); m->nparts++; } return m->nparts; } int insurecache(Mailbox *mb, Message *m) { if(m->deleted || !m->inmbox) return -1; msgincref(m); cacheidx(mb, m); if((m->cstate & Cidx) == 0){ logmsg(m, "%s: can't cache: %s: %r", mb->path, m->name); msgdecref(mb, m); return -1; } if(m->digest == nil) sysfatal("digest?"); countparts(m); return 0; }