diff options
author | Jannis Hoffmann <jannis@fehcom.de> | 2024-07-09 13:58:20 +0200 |
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committer | Jannis Hoffmann <jannis@fehcom.de> | 2024-07-09 13:58:20 +0200 |
commit | 249866e3d1e11dc72eaa1305f4bb479ded92ef38 (patch) | |
tree | 7118c5f58e29fe61c100e4d067bb90ba8d52589e /src/cdbmake.c | |
parent | 96cf8dffe4f7b0b910f790066ae622dc429eb522 (diff) |
reorganized file structure
Moved c files into src/.
Corrected VERSION file.
Removed BUILD and FILES.
Diffstat (limited to 'src/cdbmake.c')
-rw-r--r-- | src/cdbmake.c | 158 |
1 files changed, 158 insertions, 0 deletions
diff --git a/src/cdbmake.c b/src/cdbmake.c new file mode 100644 index 0000000..28e170c --- /dev/null +++ b/src/cdbmake.c @@ -0,0 +1,158 @@ +#include <unistd.h> +#include "seek.h" +#include "error.h" +#include "alloc.h" +#include "cdbread.h" +#include "cdbmake.h" + +/** + @file cdbmake.c + @author djb + @source ucspi-tcp + @brief constant data base (cdb) generation +*/ + +int cdb_make_start(struct cdb_make *c,int fd) +{ + c->head = 0; + c->split = 0; + c->hash = 0; + c->numentries = 0; + c->fd = fd; + c->pos = sizeof(c->final); + buffer_init(&c->b,write,fd,c->bspace,sizeof(c->bspace)); + return seek_set(fd,c->pos); +} + +static int posplus(struct cdb_make *c,uint32 len) +{ + uint32 newpos = c->pos + len; + if (newpos < len) { errno = ENOMEM; return -1; } + c->pos = newpos; + return 0; +} + +int cdb_make_addend(struct cdb_make *c,unsigned int keylen,unsigned int datalen,uint32 h) +{ + struct cdb_hplist *head; + + head = c->head; + if (!head || (head->num >= CDB_HPLIST)) { + head = (struct cdb_hplist *) alloc(sizeof(struct cdb_hplist)); + if (!head) return -1; + head->num = 0; + head->next = c->head; + c->head = head; + } + head->hp[head->num].h = h; + head->hp[head->num].p = c->pos; + ++head->num; + ++c->numentries; + if (posplus(c,8) == -1) return -1; + if (posplus(c,keylen) == -1) return -1; + if (posplus(c,datalen) == -1) return -1; + return 0; +} + +int cdb_make_addbegin(struct cdb_make *c,unsigned int keylen,unsigned int datalen) +{ + char buf[8]; + + if (keylen > 0xffffffff) { errno = ENOMEM; return -1; } + if (datalen > 0xffffffff) { errno = ENOMEM; return -1; } + + uint32_pack(buf,keylen); + uint32_pack(buf + 4,datalen); + if (buffer_putalign(&c->b,buf,8) == -1) return -1; + return 0; +} + +int cdb_make_add(struct cdb_make *c,char *key,unsigned int keylen,char *data,unsigned int datalen) +{ + if (cdb_make_addbegin(c,keylen,datalen) == -1) return -1; + if (buffer_putalign(&c->b,key,keylen) == -1) return -1; + if (buffer_putalign(&c->b,data,datalen) == -1) return -1; + return cdb_make_addend(c,keylen,datalen,cdb_hash(key,keylen)); +} + +int cdb_make_finish(struct cdb_make *c) +{ + char buf[8]; + int i; + uint32 len; + uint32 u; + uint32 memsize; + uint32 count; + uint32 where; + struct cdb_hplist *x; + struct cdb_hp *hp; + + for (i = 0; i < 256; ++i) + c->count[i] = 0; + + for (x = c->head; x; x = x->next) { + i = x->num; + while (i--) + ++c->count[255 & x->hp[i].h]; + } + + memsize = 1; + for (i = 0; i < 256; ++i) { + u = c->count[i] * 2; + if (u > memsize) + memsize = u; + } + + memsize += c->numentries; /* no overflow possible up to now */ + u = (uint32) 0 - (uint32) 1; + u /= sizeof(struct cdb_hp); + if (memsize > u) { errno = ENOMEM; return -1; } + + c->split = (struct cdb_hp *) alloc(memsize * sizeof(struct cdb_hp)); + if (!c->split) return -1; + + c->hash = c->split + c->numentries; + + u = 0; + for (i = 0; i < 256; ++i) { + u += c->count[i]; /* bounded by numentries, so no overflow */ + c->start[i] = u; + } + + for (x = c->head; x; x = x->next) { + i = x->num; + while (i--) + c->split[--c->start[255 & x->hp[i].h]] = x->hp[i]; + } + + for (i = 0; i < 256; ++i) { + count = c->count[i]; + + len = count + count; /* no overflow possible */ + uint32_pack(c->final + 8 * i,c->pos); + uint32_pack(c->final + 8 * i + 4,len); + + for (u = 0; u < len; ++u) + c->hash[u].h = c->hash[u].p = 0; + + hp = c->split + c->start[i]; + for (u = 0; u < count; ++u) { + where = (hp->h >> 8) % len; + while (c->hash[where].p) + if (++where == len) + where = 0; + c->hash[where] = *hp++; + } + + for (u = 0; u < len; ++u) { + uint32_pack(buf,c->hash[u].h); + uint32_pack(buf + 4,c->hash[u].p); + if (buffer_putalign(&c->b,buf,8) == -1) return -1; + if (posplus(c,8) == -1) return -1; + } + } + + if (buffer_flush(&c->b) == -1) return -1; + if (seek_begin(c->fd) == -1) return -1; + return buffer_putflush(&c->b,c->final,sizeof(c->final)); +} |