diff options
Diffstat (limited to '')
-rw-r--r-- | src/contrib/vpool/vpool.c | 241 | ||||
-rw-r--r-- | src/contrib/vpool/vpool.h | 60 |
2 files changed, 301 insertions, 0 deletions
diff --git a/src/contrib/vpool/vpool.c b/src/contrib/vpool/vpool.c new file mode 100644 index 0000000..b7c0305 --- /dev/null +++ b/src/contrib/vpool/vpool.c @@ -0,0 +1,241 @@ +/* + * Copyright (c) 2006, 2008 Alexey Vatchenko <av@bsdua.org> + * + * Permission to use, copy, modify, and/or distribute this software for any + * purpose with or without fee is hereby granted, provided that the above + * copyright notice and this permission notice appear in all copies. + * + * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES + * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF + * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR + * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES + * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN + * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF + * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. + */ + +#include <sys/types.h> + +#include <errno.h> +#include <limits.h> +#include <stdint.h> +#include <stdlib.h> +#include <string.h> + +#include "contrib/vpool/vpool.h" + +static void vpool_shift(struct vpool *pool); +static int vpool_new_size(struct vpool *pool, size_t datsize, + size_t *size); +static int vpool_resize(struct vpool *pool, size_t datsize); + +static void +vpool_shift(struct vpool *pool) +{ + if (pool->v_buf != pool->v_basebuf) { + memmove(pool->v_basebuf, pool->v_buf, pool->v_off); + pool->v_buf = pool->v_basebuf; + } +} + +static int +vpool_new_size(struct vpool *pool, size_t datsize, size_t *size) +{ + size_t need; + size_t rem; + + if (datsize <= pool->v_size - pool->v_off) { + *size = pool->v_size; + return (0); + } + + /* Check limit of new requested size */ + if (pool->v_limit - pool->v_off < datsize) { + return (EFBIG); + } + need = pool->v_off + datsize; + + /* Check limit of new size aligned to block size */ + rem = need % pool->v_blksize; + if (rem != 0) { + if (pool->v_limit - pool->v_off >= + datsize + (pool->v_blksize - rem)) { + need += pool->v_blksize - rem; + } else { + need = pool->v_limit; + } + } + + *size = need; + return (0); +} + +static int +vpool_resize(struct vpool *pool, size_t datsize) +{ + void *ret; + size_t size; + int error; + + error = vpool_new_size(pool, datsize, &size); + if (error != 0) { + return (error); + } + + if (size > pool->v_size) { + ret = malloc(size); + if (ret == NULL) { + return (ENOMEM); + } + + memcpy(ret, pool->v_buf, pool->v_off); + free(pool->v_basebuf); + pool->v_basebuf = pool->v_buf = ret; + pool->v_size = size; + } else if ((pool->v_size - pool->v_off) - + (pool->v_buf - pool->v_basebuf) < datsize) { + vpool_shift(pool); + } + + return (0); +} + +void +vpool_init(struct vpool *pool, size_t blksize, size_t limit) +{ + + pool->v_basebuf = pool->v_buf = NULL; + pool->v_off = pool->v_size = 0; + + pool->v_blksize = (blksize == 0) ? 4096 : blksize; /* XXX */ + pool->v_limit = (limit == 0) ? SIZE_MAX : limit; + + pool->v_lasterr = 0; +} + +void +vpool_final(struct vpool *pool) +{ + free(pool->v_basebuf); +} + +void +vpool_reset(struct vpool *pool) +{ + free(pool->v_basebuf); + pool->v_basebuf = pool->v_buf = NULL; + pool->v_off = pool->v_size = 0; + pool->v_lasterr = 0; +} + +void +vpool_wipe(struct vpool *pool) +{ + pool->v_off = 0; + pool->v_lasterr = 0; +} + +void * +vpool_insert(struct vpool *pool, size_t where, void *data, size_t datsize) +{ + void *ret; + int error; + + error = vpool_resize(pool, datsize); + if (error != 0) { + pool->v_lasterr = error; + return (NULL); + } + + /* + * If ``where'' is greater than or equal to offset then + * we are appending data to the end of the buffer. + */ + if (where > pool->v_off) { + where = pool->v_off; + } + + ret = (uint8_t *)pool->v_buf + where; + if (pool->v_off - where > 0) { + memmove(ret + datsize, ret, pool->v_off - where); + } + memcpy(ret, data, datsize); + pool->v_off += datsize; + pool->v_lasterr = 0; + + return (ret); +} + +void * +vpool_expand(struct vpool *pool, size_t where, size_t size) +{ + void *ret; + int error; + + error = vpool_resize(pool, size); + if (error != 0) { + pool->v_lasterr = error; + return (NULL); + } + + /* + * If ``where'' is greater than or equal to offset then + * we are appending data to the end of the buffer. + */ + if (where > pool->v_off) { + where = pool->v_off; + } + + ret = (uint8_t *)pool->v_buf + where; + if (pool->v_off - where > 0) { + memmove(ret + size, ret, pool->v_off - where); + } + pool->v_off += size; + pool->v_lasterr = 0; + + return (ret); +} + +int +vpool_truncate(struct vpool *pool, + size_t where, size_t size, enum vpool_trunc how) +{ + /* Check if caller wants to remove more data than we have */ + if (where >= pool->v_off || + size > pool->v_off || pool->v_off - size < where) { + pool->v_lasterr = ERANGE; + return (pool->v_lasterr); + } + + if (how == VPOOL_EXCLUDE) { + if (where == 0) { + /* + * Optimization. + * Don't move data, just adjust pointer. + */ + pool->v_buf = (uint8_t *)pool->v_buf + size; + } else { + memmove((uint8_t *)pool->v_buf + where, + (uint8_t *)pool->v_buf + where + size, + pool->v_off - size - where); + } + pool->v_off -= size; + } else { + pool->v_buf = (uint8_t *)pool->v_buf + where; + pool->v_off = size; + } + + pool->v_lasterr = 0; + return (0); +} + +void +vpool_export(struct vpool *pool, void **buf, size_t *size) +{ + vpool_shift(pool); + *buf = pool->v_buf; + *size = pool->v_off; + pool->v_basebuf = pool->v_buf = NULL; + pool->v_off = pool->v_size = 0; + pool->v_lasterr = 0; +} diff --git a/src/contrib/vpool/vpool.h b/src/contrib/vpool/vpool.h new file mode 100644 index 0000000..82e3d66 --- /dev/null +++ b/src/contrib/vpool/vpool.h @@ -0,0 +1,60 @@ +/* + * Copyright (c) 2006, 2008 Alexey Vatchenko <av@bsdua.org> + * + * Permission to use, copy, modify, and/or distribute this software for any + * purpose with or without fee is hereby granted, provided that the above + * copyright notice and this permission notice appear in all copies. + * + * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES + * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF + * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR + * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES + * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN + * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF + * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. + */ + +/* + * VPool: implementation of pool of data with a variable size. + */ +#ifndef _VPOOL_H_ +#define _VPOOL_H_ + +#include <stddef.h> +#include <limits.h> + +struct vpool { + void *v_basebuf; /* pointer returned by (re|m)alloc() */ + void *v_buf; /* actual data starts here */ + size_t v_off; + size_t v_size; + + size_t v_blksize; + size_t v_limit; + int v_lasterr; +}; + +enum vpool_trunc {VPOOL_EXCLUDE, VPOOL_INCLUDE}; +#define VPOOL_TAIL UINT_MAX + +void vpool_init(struct vpool *pool, size_t blksize, size_t limit); +void vpool_final(struct vpool *pool); + +void vpool_reset(struct vpool *pool); +void vpool_wipe(struct vpool *pool); + +void * vpool_insert(struct vpool *pool, + size_t where, void *data, size_t datsize); +void * vpool_expand(struct vpool *pool, size_t where, size_t size); + +int vpool_truncate(struct vpool *pool, + size_t where, size_t size, enum vpool_trunc how); + +#define vpool_is_empty(pool) ((pool)->v_off == 0) +#define vpool_get_buf(pool) ((pool)->v_buf) +#define vpool_get_length(pool) ((pool)->v_off) +#define vpool_get_error(pool) ((pool)->v_lasterr) + +void vpool_export(struct vpool *pool, void **buf, size_t *size); + +#endif /* !_VPOOL_H_ */ |