ccid/src/simclist.c

1587 lines
49 KiB
C

/*
* Copyright (c) 2007,2008,2009,2010,2011 Mij <mij@bitchx.it>
*
* Permission to use, copy, modify, and 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.
*/
/*
* SimCList library. See http://mij.oltrelinux.com/devel/simclist
*/
/* SimCList implementation, version 1.6 */
#include <stdlib.h>
#include <string.h>
#include <errno.h> /* for setting errno */
#include <sys/types.h>
#ifndef _WIN32
/* not in Windows! */
# include <unistd.h>
# include <stdint.h>
#endif
#ifndef SIMCLIST_NO_DUMPRESTORE
/* includes for dump/restore */
# include <time.h>
# include <sys/uio.h> /* for READ_ERRCHECK() and write() */
# include <fcntl.h> /* for open() etc */
# ifndef _WIN32
# include <arpa/inet.h> /* for htons() on UNIX */
# else
# include <winsock2.h> /* for htons() on Windows */
# endif
#endif
/* disable asserts */
#ifndef SIMCLIST_DEBUG
#define NDEBUG
#endif
#include <assert.h>
#include <sys/stat.h> /* for open()'s access modes S_IRUSR etc */
#include <limits.h>
#if defined(_MSC_VER) || defined(__MINGW32__)
/* provide gettimeofday() missing in Windows */
int gettimeofday(struct timeval *tp, void *tzp) {
DWORD t;
/* XSI says: "If tzp is not a null pointer, the behavior is unspecified" */
assert(tzp == NULL);
t = timeGetTime();
tp->tv_sec = t / 1000;
tp->tv_usec = t % 1000;
return 0;
}
#endif
/* work around lack of inttypes.h support in broken Microsoft Visual Studio compilers */
#if !defined(_WIN32) || !defined(_MSC_VER)
# include <inttypes.h> /* (u)int*_t */
#else
# include <basetsd.h>
typedef UINT8 uint8_t;
typedef UINT16 uint16_t;
typedef ULONG32 uint32_t;
typedef UINT64 uint64_t;
typedef INT8 int8_t;
typedef INT16 int16_t;
typedef LONG32 int32_t;
typedef INT64 int64_t;
#endif
/* define some commodity macros for Dump/Restore functionality */
#ifndef SIMCLIST_NO_DUMPRESTORE
/* write() decorated with error checking logic */
#define WRITE_ERRCHECK(fd, msgbuf, msglen) do { \
if (write(fd, msgbuf, msglen) < 0) return -1; \
} while (0);
/* READ_ERRCHECK() decorated with error checking logic */
#define READ_ERRCHECK(fd, msgbuf, msglen) do { \
if (read(fd, msgbuf, msglen) != msglen) { \
/*errno = EPROTO;*/ \
return -1; \
} \
} while (0);
/* convert 64bit integers from host to network format */
#define hton64(x) (\
htons(1) == 1 ? \
(uint64_t)x /* big endian */ \
: /* little endian */ \
((uint64_t)((((uint64_t)(x) & 0xff00000000000000ULL) >> 56) | \
(((uint64_t)(x) & 0x00ff000000000000ULL) >> 40) | \
(((uint64_t)(x) & 0x0000ff0000000000ULL) >> 24) | \
(((uint64_t)(x) & 0x000000ff00000000ULL) >> 8) | \
(((uint64_t)(x) & 0x00000000ff000000ULL) << 8) | \
(((uint64_t)(x) & 0x0000000000ff0000ULL) << 24) | \
(((uint64_t)(x) & 0x000000000000ff00ULL) << 40) | \
(((uint64_t)(x) & 0x00000000000000ffULL) << 56))) \
)
/* convert 64bit integers from network to host format */
#define ntoh64(x) (hton64(x))
#endif
/* some OSes don't have EPROTO (eg OpenBSD) */
#ifndef EPROTO
#define EPROTO EIO
#endif
#ifdef SIMCLIST_WITH_THREADS
/* limit (approx) to the number of threads running
* for threaded operations. Only meant when
* SIMCLIST_WITH_THREADS is defined */
#define SIMCLIST_MAXTHREADS 2
#endif
/*
* how many elems to keep as spare. During a deletion, an element
* can be saved in a "free-list", not free()d immediately. When
* latter insertions are performed, spare elems can be used instead
* of malloc()ing new elems.
*
* about this param, some values for appending
* 10 million elems into an empty list:
* (#, time[sec], gain[%], gain/no[%])
* 0 2,164 0,00 0,00 <-- feature disabled
* 1 1,815 34,9 34,9
* 2 1,446 71,8 35,9 <-- MAX gain/no
* 3 1,347 81,7 27,23
* 5 1,213 95,1 19,02
* 8 1,064 110,0 13,75
* 10 1,015 114,9 11,49 <-- MAX gain w/ likely sol
* 15 1,019 114,5 7,63
* 25 0,985 117,9 4,72
* 50 1,088 107,6 2,15
* 75 1,016 114,8 1,53
* 100 0,988 117,6 1,18
* 150 1,022 114,2 0,76
* 200 0,939 122,5 0,61 <-- MIN time
*/
#ifndef SIMCLIST_MAX_SPARE_ELEMS
#define SIMCLIST_MAX_SPARE_ELEMS 5
#endif
#ifdef SIMCLIST_WITH_THREADS
#include <pthread.h>
#endif
#include "simclist.h"
/* minumum number of elements for sorting with quicksort instead of insertion */
#define SIMCLIST_MINQUICKSORTELS 24
/* list dump declarations */
#define SIMCLIST_DUMPFORMAT_VERSION 1 /* (short integer) version of fileformat managed by _dump* and _restore* functions */
#define SIMCLIST_DUMPFORMAT_HEADERLEN 30 /* length of the header */
/* header for a list dump */
struct list_dump_header_s {
uint16_t ver; /* version */
int32_t timestamp_sec; /* dump timestamp, seconds since UNIX Epoch */
int32_t timestamp_usec; /* dump timestamp, microseconds since timestamp_sec */
int32_t rndterm; /* random value terminator -- terminates the data sequence */
uint32_t totlistlen; /* sum of every element' size, bytes */
uint32_t numels; /* number of elements */
uint32_t elemlen; /* bytes length of an element, for constant-size lists, <= 0 otherwise */
int32_t listhash; /* hash of the list at the time of dumping, or 0 if to be ignored */
};
/* deletes tmp from list, with care wrt its position (head, tail, middle) */
static int list_drop_elem(list_t *restrict l, struct list_entry_s *tmp, unsigned int pos);
/* set default values for initialized lists */
static int list_attributes_setdefaults(list_t *restrict l);
#ifndef NDEBUG
/* check whether the list internal REPresentation is valid -- Costs O(n) */
static int list_repOk(const list_t *restrict l);
/* check whether the list attribute set is valid -- Costs O(1) */
static int list_attrOk(const list_t *restrict l);
#endif
/* do not inline, this is recursive */
static void list_sort_quicksort(list_t *restrict l, int versus,
unsigned int first, struct list_entry_s *fel,
unsigned int last, struct list_entry_s *lel);
static inline void list_sort_selectionsort(list_t *restrict l, int versus,
unsigned int first, struct list_entry_s *fel,
unsigned int last, struct list_entry_s *lel);
static void *list_get_minmax(const list_t *restrict l, int versus);
static inline struct list_entry_s *list_findpos(const list_t *restrict l, int posstart);
/*
* Random Number Generator
*
* The user is expected to seed the RNG (ie call srand()) if
* SIMCLIST_SYSTEM_RNG is defined.
*
* Otherwise, a self-contained RNG based on LCG is used; see
* http://en.wikipedia.org/wiki/Linear_congruential_generator .
*
* Facts pro local RNG:
* 1. no need for the user to call srand() on his own
* 2. very fast, possibly faster than OS
* 3. avoid interference with user's RNG
*
* Facts pro system RNG:
* 1. may be more accurate (irrelevant for SimCList randno purposes)
* 2. why reinvent the wheel
*
* Default to local RNG for user's ease of use.
*/
#ifdef SIMCLIST_SYSTEM_RNG
/* keep track whether we initialized already (non-0) or not (0) */
static unsigned random_seed = 0;
/* use local RNG */
static inline void seed_random(void) {
if (random_seed == 0)
random_seed = (unsigned)getpid() ^ (unsigned)time(NULL);
}
static inline long get_random(void) {
random_seed = (1664525 * random_seed + 1013904223);
return random_seed;
}
#else
/* use OS's random generator */
# define seed_random()
# define get_random() (rand())
#endif
/* list initialization */
int list_init(list_t *restrict l) {
if (l == NULL) return -1;
memset(l, 0, sizeof *l);
seed_random();
l->numels = 0;
/* head/tail sentinels and mid pointer */
l->head_sentinel = (struct list_entry_s *)malloc(sizeof(struct list_entry_s));
l->tail_sentinel = (struct list_entry_s *)malloc(sizeof(struct list_entry_s));
if (NULL == l->tail_sentinel || NULL == l->head_sentinel)
return -1;
l->head_sentinel->next = l->tail_sentinel;
l->tail_sentinel->prev = l->head_sentinel;
l->head_sentinel->prev = l->tail_sentinel->next = l->mid = NULL;
l->head_sentinel->data = l->tail_sentinel->data = NULL;
/* iteration attributes */
l->iter_active = 0;
l->iter_pos = 0;
l->iter_curentry = NULL;
/* free-list attributes */
l->spareels = (struct list_entry_s **)malloc(SIMCLIST_MAX_SPARE_ELEMS * sizeof(struct list_entry_s *));
l->spareelsnum = 0;
if (NULL == l->spareels)
return -1;
#ifdef SIMCLIST_WITH_THREADS
l->threadcount = 0;
#endif
if (list_attributes_setdefaults(l))
return -1;
assert(list_repOk(l));
assert(list_attrOk(l));
return 0;
}
void list_destroy(list_t *restrict l) {
unsigned int i;
list_clear(l);
for (i = 0; i < l->spareelsnum; i++) {
free(l->spareels[i]);
}
free(l->spareels);
free(l->head_sentinel);
free(l->tail_sentinel);
}
int list_attributes_setdefaults(list_t *restrict l) {
l->attrs.comparator = NULL;
l->attrs.seeker = NULL;
/* also free() element data when removing and element from the list */
l->attrs.meter = NULL;
l->attrs.copy_data = 0;
l->attrs.hasher = NULL;
/* serializer/unserializer */
l->attrs.serializer = NULL;
l->attrs.unserializer = NULL;
assert(list_attrOk(l));
return 0;
}
/* setting list properties */
int list_attributes_comparator(list_t *restrict l, element_comparator comparator_fun) {
if (l == NULL) return -1;
l->attrs.comparator = comparator_fun;
assert(list_attrOk(l));
return 0;
}
int list_attributes_seeker(list_t *restrict l, element_seeker seeker_fun) {
if (l == NULL) return -1;
l->attrs.seeker = seeker_fun;
assert(list_attrOk(l));
return 0;
}
int list_attributes_copy(list_t *restrict l, element_meter metric_fun, int copy_data) {
if (l == NULL || (metric_fun == NULL && copy_data != 0)) return -1;
l->attrs.meter = metric_fun;
l->attrs.copy_data = copy_data;
assert(list_attrOk(l));
return 0;
}
int list_attributes_hash_computer(list_t *restrict l, element_hash_computer hash_computer_fun) {
if (l == NULL) return -1;
l->attrs.hasher = hash_computer_fun;
assert(list_attrOk(l));
return 0;
}
int list_attributes_serializer(list_t *restrict l, element_serializer serializer_fun) {
if (l == NULL) return -1;
l->attrs.serializer = serializer_fun;
assert(list_attrOk(l));
return 0;
}
int list_attributes_unserializer(list_t *restrict l, element_unserializer unserializer_fun) {
if (l == NULL) return -1;
l->attrs.unserializer = unserializer_fun;
assert(list_attrOk(l));
return 0;
}
int list_append(list_t *restrict l, const void *data) {
return list_insert_at(l, data, l->numels);
}
int list_prepend(list_t *restrict l, const void *data) {
return list_insert_at(l, data, 0);
}
void *list_fetch(list_t *restrict l) {
return list_extract_at(l, 0);
}
void *list_get_at(const list_t *restrict l, unsigned int pos) {
struct list_entry_s *tmp;
tmp = list_findpos(l, pos);
return (tmp != NULL ? tmp->data : NULL);
}
void *list_get_max(const list_t *restrict l) {
return list_get_minmax(l, +1);
}
void *list_get_min(const list_t *restrict l) {
return list_get_minmax(l, -1);
}
/* REQUIRES {list->numels >= 1}
* return the min (versus < 0) or max value (v > 0) in l */
static void *list_get_minmax(const list_t *restrict l, int versus) {
void *curminmax;
struct list_entry_s *s;
if (l->attrs.comparator == NULL || l->numels == 0)
return NULL;
curminmax = l->head_sentinel->next->data;
for (s = l->head_sentinel->next->next; s != l->tail_sentinel; s = s->next) {
if (l->attrs.comparator(curminmax, s->data) * versus > 0)
curminmax = s->data;
}
return curminmax;
}
/* set tmp to point to element at index posstart in l */
static inline struct list_entry_s *list_findpos(const list_t *restrict l, int posstart) {
struct list_entry_s *ptr;
float x;
int i;
if (NULL == l->head_sentinel || NULL == l->tail_sentinel)
return NULL;
/* accept 1 slot overflow for fetching head and tail sentinels */
if (posstart < -1 || posstart > (int)l->numels) return NULL;
if( l->numels != 0 )
x = (float)(posstart+1) / l->numels;
else
x = 1;
if (x <= 0.25) {
/* first quarter: get to posstart from head */
for (i = -1, ptr = l->head_sentinel; i < posstart; ptr = ptr->next, i++);
} else if (x < 0.5) {
/* second quarter: get to posstart from mid */
for (i = (l->numels-1)/2, ptr = l->mid; i > posstart; ptr = ptr->prev, i--);
} else if (x <= 0.75) {
/* third quarter: get to posstart from mid */
for (i = (l->numels-1)/2, ptr = l->mid; i < posstart; ptr = ptr->next, i++);
} else {
/* fourth quarter: get to posstart from tail */
for (i = l->numels, ptr = l->tail_sentinel; i > posstart; ptr = ptr->prev, i--);
}
return ptr;
}
void *list_extract_at(list_t *restrict l, unsigned int pos) {
struct list_entry_s *tmp;
void *data;
if (l->iter_active || pos >= l->numels) return NULL;
tmp = list_findpos(l, pos);
if (NULL == tmp)
return NULL;
data = tmp->data;
tmp->data = NULL; /* save data from list_drop_elem() free() */
list_drop_elem(l, tmp, pos);
l->numels--;
assert(list_repOk(l));
return data;
}
int list_insert_at(list_t *restrict l, const void *data, unsigned int pos) {
struct list_entry_s *lent, *succ, *prec;
if (l->iter_active || pos > l->numels) return -1;
/* this code optimizes malloc() with a free-list */
if (l->spareelsnum > 0) {
lent = l->spareels[l->spareelsnum-1];
l->spareelsnum--;
} else {
lent = (struct list_entry_s *)malloc(sizeof(struct list_entry_s));
if (lent == NULL)
return -1;
}
if (l->attrs.copy_data) {
/* make room for user' data (has to be copied) */
size_t datalen = l->attrs.meter(data);
lent->data = (struct list_entry_s *)malloc(datalen);
if (NULL == lent->data)
{
free(lent);
return -1;
}
memcpy(lent->data, data, datalen);
} else {
lent->data = (void*)data;
}
/* actually append element */
prec = list_findpos(l, pos-1);
if (NULL == prec)
{
free(lent->data);
free(lent);
return -1;
}
succ = prec->next;
prec->next = lent;
lent->prev = prec;
lent->next = succ;
succ->prev = lent;
l->numels++;
/* fix mid pointer */
if (l->numels == 1) { /* first element, set pointer */
l->mid = lent;
} else if (l->numels % 2) { /* now odd */
if (pos >= (l->numels-1)/2) l->mid = l->mid->next;
} else { /* now even */
if (pos <= (l->numels-1)/2) l->mid = l->mid->prev;
}
assert(list_repOk(l));
return 1;
}
int list_delete(list_t *restrict l, const void *data) {
int pos, r;
pos = list_locate(l, data);
if (pos < 0)
return -1;
r = list_delete_at(l, pos);
if (r < 0)
return -1;
assert(list_repOk(l));
return 0;
}
int list_delete_at(list_t *restrict l, unsigned int pos) {
struct list_entry_s *delendo;
if (l->iter_active || pos >= l->numels) return -1;
delendo = list_findpos(l, pos);
list_drop_elem(l, delendo, pos);
l->numels--;
assert(list_repOk(l));
return 0;
}
int list_delete_range(list_t *restrict l, unsigned int posstart, unsigned int posend) {
struct list_entry_s *lastvalid, *tmp, *tmp2;
unsigned int numdel, midposafter, i;
int movedx;
if (l->iter_active || posend < posstart || posend >= l->numels) return -1;
numdel = posend - posstart + 1;
if (numdel == l->numels) return list_clear(l);
tmp = list_findpos(l, posstart); /* first el to be deleted */
lastvalid = tmp->prev; /* last valid element */
midposafter = (l->numels-1-numdel)/2;
midposafter = midposafter < posstart ? midposafter : midposafter+numdel;
movedx = midposafter - (l->numels-1)/2;
if (movedx > 0) { /* move right */
for (i = 0; i < (unsigned int)movedx; l->mid = l->mid->next, i++);
} else { /* move left */
movedx = -movedx;
for (i = 0; i < (unsigned int)movedx; l->mid = l->mid->prev, i++);
}
assert(posstart == 0 || lastvalid != l->head_sentinel);
i = posstart;
if (l->attrs.copy_data) {
/* also free element data */
for (; i <= posend; i++) {
tmp2 = tmp;
tmp = tmp->next;
if (tmp2->data != NULL) free(tmp2->data);
if (l->spareelsnum < SIMCLIST_MAX_SPARE_ELEMS) {
l->spareels[l->spareelsnum++] = tmp2;
} else {
free(tmp2);
}
}
} else {
/* only free containers */
for (; i <= posend; i++) {
tmp2 = tmp;
tmp = tmp->next;
if (l->spareelsnum < SIMCLIST_MAX_SPARE_ELEMS) {
l->spareels[l->spareelsnum++] = tmp2;
} else {
free(tmp2);
}
}
}
assert(i == posend+1 && (posend != l->numels || tmp == l->tail_sentinel));
lastvalid->next = tmp;
tmp->prev = lastvalid;
l->numels -= posend - posstart + 1;
assert(list_repOk(l));
return numdel;
}
int list_clear(list_t *restrict l) {
struct list_entry_s *s;
unsigned int numels;
/* will be returned */
numels = l->numels;
if (l->iter_active) return -1;
if (l->head_sentinel && l->tail_sentinel) {
if (l->attrs.copy_data) { /* also free user data */
/* spare a loop conditional with two loops: spareing elems and freeing elems */
for (s = l->head_sentinel->next; l->spareelsnum < SIMCLIST_MAX_SPARE_ELEMS && s != l->tail_sentinel; s = s->next) {
/* move elements as spares as long as there is room */
if (s->data != NULL) free(s->data);
l->spareels[l->spareelsnum++] = s;
}
while (s != l->tail_sentinel) {
/* free the remaining elems */
if (s->data != NULL) free(s->data);
s = s->next;
free(s->prev);
}
l->head_sentinel->next = l->tail_sentinel;
l->tail_sentinel->prev = l->head_sentinel;
} else { /* only free element containers */
/* spare a loop conditional with two loops: spareing elems and freeing elems */
for (s = l->head_sentinel->next; l->spareelsnum < SIMCLIST_MAX_SPARE_ELEMS && s != l->tail_sentinel; s = s->next) {
/* move elements as spares as long as there is room */
l->spareels[l->spareelsnum++] = s;
}
while (s != l->tail_sentinel) {
/* free the remaining elems */
s = s->next;
free(s->prev);
}
l->head_sentinel->next = l->tail_sentinel;
l->tail_sentinel->prev = l->head_sentinel;
}
}
l->numels = 0;
l->mid = NULL;
assert(list_repOk(l));
return numels;
}
unsigned int list_size(const list_t *restrict l) {
return l->numels;
}
int list_empty(const list_t *restrict l) {
return (l->numels == 0);
}
int list_locate(const list_t *restrict l, const void *data) {
struct list_entry_s *el;
int pos = 0;
if (NULL == l->head_sentinel || NULL == l->tail_sentinel)
return -1;
if (l->attrs.comparator != NULL) {
/* use comparator */
for (el = l->head_sentinel->next; el != l->tail_sentinel; el = el->next, pos++) {
if (l->attrs.comparator(data, el->data) == 0) break;
}
} else {
/* compare references */
for (el = l->head_sentinel->next; el != l->tail_sentinel; el = el->next, pos++) {
if (el->data == data) break;
}
}
if (el == l->tail_sentinel) return -1;
return pos;
}
void *list_seek(list_t *restrict l, const void *indicator) {
const struct list_entry_s *iter;
if (l->attrs.seeker == NULL) return NULL;
if (NULL == l->head_sentinel || NULL == l->tail_sentinel)
return NULL;
for (iter = l->head_sentinel->next; iter != l->tail_sentinel; iter = iter->next) {
if (l->attrs.seeker(iter->data, indicator) != 0) return iter->data;
}
return NULL;
}
int list_contains(const list_t *restrict l, const void *data) {
return (list_locate(l, data) >= 0);
}
int list_concat(const list_t *l1, const list_t *l2, list_t *restrict dest) {
struct list_entry_s *el, *srcel;
unsigned int cnt;
int err;
if (l1 == NULL || l2 == NULL || dest == NULL || l1 == dest || l2 == dest)
return -1;
if (NULL == l1->head_sentinel || NULL == l1->tail_sentinel
|| NULL == l2->head_sentinel || NULL == l2->tail_sentinel)
return -1;
if (list_init(dest))
return -1;
dest->numels = l1->numels + l2->numels;
if (dest->numels == 0)
return 0;
/* copy list1 */
srcel = l1->head_sentinel->next;
el = dest->head_sentinel;
while (srcel != l1->tail_sentinel) {
el->next = (struct list_entry_s *)malloc(sizeof(struct list_entry_s));
if (NULL == el->next)
return -1;
el->next->prev = el;
el = el->next;
el->data = srcel->data;
srcel = srcel->next;
}
dest->mid = el; /* approximate position (adjust later) */
/* copy list 2 */
srcel = l2->head_sentinel->next;
while (srcel != l2->tail_sentinel) {
el->next = (struct list_entry_s *)malloc(sizeof(struct list_entry_s));
if (NULL == el->next)
return -1;
el->next->prev = el;
el = el->next;
el->data = srcel->data;
srcel = srcel->next;
}
el->next = dest->tail_sentinel;
dest->tail_sentinel->prev = el;
/* fix mid pointer */
err = l2->numels - l1->numels;
if ((err+1)/2 > 0) { /* correct pos RIGHT (err-1)/2 moves */
err = (err+1)/2;
for (cnt = 0; cnt < (unsigned int)err; cnt++) dest->mid = dest->mid->next;
} else if (err/2 < 0) { /* correct pos LEFT (err/2)-1 moves */
err = -err/2;
for (cnt = 0; cnt < (unsigned int)err; cnt++) dest->mid = dest->mid->prev;
}
assert(!(list_repOk(l1) && list_repOk(l2)) || list_repOk(dest));
return 0;
}
int list_sort(list_t *restrict l, int versus) {
if (l->iter_active || l->attrs.comparator == NULL) /* cannot modify list in the middle of an iteration */
return -1;
if (l->numels <= 1)
return 0;
if (NULL == l->head_sentinel || NULL == l->tail_sentinel)
return -1;
list_sort_quicksort(l, versus, 0, l->head_sentinel->next, l->numels-1, l->tail_sentinel->prev);
assert(list_repOk(l));
return 0;
}
#ifdef SIMCLIST_WITH_THREADS
struct list_sort_wrappedparams {
list_t *restrict l;
int versus;
unsigned int first, last;
struct list_entry_s *fel, *lel;
};
static void *list_sort_quicksort_threadwrapper(void *wrapped_params) {
struct list_sort_wrappedparams *wp = (struct list_sort_wrappedparams *)wrapped_params;
list_sort_quicksort(wp->l, wp->versus, wp->first, wp->fel, wp->last, wp->lel);
free(wp);
pthread_exit(NULL);
return NULL;
}
#endif
static inline void list_sort_selectionsort(list_t *restrict l, int versus,
unsigned int first, struct list_entry_s *fel,
unsigned int last, struct list_entry_s *lel) {
struct list_entry_s *cursor, *toswap, *firstunsorted;
void *tmpdata;
if (last <= first) /* <= 1-element lists are always sorted */
return;
for (firstunsorted = fel; firstunsorted != lel; firstunsorted = firstunsorted->next) {
/* find min or max in the remainder of the list */
for (toswap = firstunsorted, cursor = firstunsorted->next; cursor != lel->next; cursor = cursor->next)
if (l->attrs.comparator(toswap->data, cursor->data) * -versus > 0) toswap = cursor;
if (toswap != firstunsorted) { /* swap firstunsorted with toswap */
tmpdata = firstunsorted->data;
firstunsorted->data = toswap->data;
toswap->data = tmpdata;
}
}
}
static void list_sort_quicksort(list_t *restrict l, int versus,
unsigned int first, struct list_entry_s *fel,
unsigned int last, struct list_entry_s *lel) {
unsigned int pivotid;
unsigned int i;
register struct list_entry_s *pivot;
struct list_entry_s *left, *right;
void *tmpdata;
#ifdef SIMCLIST_WITH_THREADS
pthread_t tid;
int traised;
#endif
if (last <= first) /* <= 1-element lists are always sorted */
return;
if (last - first+1 <= SIMCLIST_MINQUICKSORTELS) {
list_sort_selectionsort(l, versus, first, fel, last, lel);
return;
}
/* base of iteration: one element list */
if (! (last > first)) return;
pivotid = (get_random() % (last - first + 1));
/* pivotid = (last - first + 1) / 2; */
/* find pivot */
if (pivotid < (last - first + 1)/2) {
for (i = 0, pivot = fel; i < pivotid; pivot = pivot->next, i++);
} else {
for (i = last - first, pivot = lel; i > pivotid; pivot = pivot->prev, i--);
}
/* smaller PIVOT bigger */
left = fel;
right = lel;
/* iterate --- left ---> PIV <--- right --- */
while (left != pivot && right != pivot) {
for (; left != pivot && (l->attrs.comparator(left->data, pivot->data) * -versus <= 0); left = left->next);
/* left points to a smaller element, or to pivot */
for (; right != pivot && (l->attrs.comparator(right->data, pivot->data) * -versus >= 0); right = right->prev);
/* right points to a bigger element, or to pivot */
if (left != pivot && right != pivot) {
/* swap, then move iterators */
tmpdata = left->data;
left->data = right->data;
right->data = tmpdata;
left = left->next;
right = right->prev;
}
}
/* now either left points to pivot (end run), or right */
if (right == pivot) { /* left part longer */
while (left != pivot) {
if (l->attrs.comparator(left->data, pivot->data) * -versus > 0) {
tmpdata = left->data;
left->data = pivot->prev->data;
pivot->prev->data = pivot->data;
pivot->data = tmpdata;
pivot = pivot->prev;
pivotid--;
if (pivot == left) break;
} else {
left = left->next;
}
}
} else { /* right part longer */
while (right != pivot) {
if (l->attrs.comparator(right->data, pivot->data) * -versus < 0) {
/* move current right before pivot */
tmpdata = right->data;
right->data = pivot->next->data;
pivot->next->data = pivot->data;
pivot->data = tmpdata;
pivot = pivot->next;
pivotid++;
if (pivot == right) break;
} else {
right = right->prev;
}
}
}
/* sort sublists A and B : |---A---| pivot |---B---| */
#ifdef SIMCLIST_WITH_THREADS
traised = 0;
if (pivotid > 0) {
/* prepare wrapped args, then start thread */
if (l->threadcount < SIMCLIST_MAXTHREADS-1) {
struct list_sort_wrappedparams *wp = (struct list_sort_wrappedparams *)malloc(sizeof(struct list_sort_wrappedparams));
if (NULL == wp)
return -1;
l->threadcount++;
traised = 1;
wp->l = l;
wp->versus = versus;
wp->first = first;
wp->fel = fel;
wp->last = first+pivotid-1;
wp->lel = pivot->prev;
if (pthread_create(&tid, NULL, list_sort_quicksort_threadwrapper, wp) != 0) {
free(wp);
traised = 0;
list_sort_quicksort(l, versus, first, fel, first+pivotid-1, pivot->prev);
}
} else {
list_sort_quicksort(l, versus, first, fel, first+pivotid-1, pivot->prev);
}
}
if (first + pivotid < last) list_sort_quicksort(l, versus, first+pivotid+1, pivot->next, last, lel);
if (traised) {
pthread_join(tid, (void **)NULL);
l->threadcount--;
}
#else
if (pivotid > 0) list_sort_quicksort(l, versus, first, fel, first+pivotid-1, pivot->prev);
if (first + pivotid < last) list_sort_quicksort(l, versus, first+pivotid+1, pivot->next, last, lel);
#endif
}
int list_iterator_start(list_t *restrict l) {
if (l->iter_active) return 0;
if (NULL == l->head_sentinel)
return -1;
l->iter_pos = 0;
l->iter_active = 1;
l->iter_curentry = l->head_sentinel->next;
return 1;
}
void *list_iterator_next(list_t *restrict l) {
void *toret;
if (! l->iter_active) return NULL;
toret = l->iter_curentry->data;
l->iter_curentry = l->iter_curentry->next;
l->iter_pos++;
return toret;
}
int list_iterator_hasnext(const list_t *restrict l) {
if (! l->iter_active) return 0;
return (l->iter_pos < l->numels);
}
int list_iterator_stop(list_t *restrict l) {
if (! l->iter_active) return 0;
l->iter_pos = 0;
l->iter_active = 0;
return 1;
}
int list_hash(const list_t *restrict l, list_hash_t *restrict hash) {
struct list_entry_s *x;
list_hash_t tmphash;
assert(hash != NULL);
tmphash = l->numels * 2 + 100;
if (l->attrs.hasher == NULL) {
#ifdef SIMCLIST_ALLOW_LOCATIONBASED_HASHES
/* ENABLE WITH CARE !! */
#warning "Memlocation-based hash is consistent only for testing modification in the same program run."
int i;
/* only use element references */
for (x = l->head_sentinel->next; x != l->tail_sentinel; x = x->next) {
for (i = 0; i < sizeof(x->data); i++) {
tmphash += (tmphash ^ (uintptr_t)x->data);
}
tmphash += tmphash % l->numels;
}
#else
return -1;
#endif
} else {
/* hash each element with the user-given function */
for (x = l->head_sentinel->next; x != l->tail_sentinel; x = x->next) {
tmphash += tmphash ^ l->attrs.hasher(x->data);
tmphash += tmphash % l->numels;
}
}
*hash = tmphash;
return 0;
}
#ifndef SIMCLIST_NO_DUMPRESTORE
int list_dump_getinfo_filedescriptor(int fd, list_dump_info_t *restrict info) {
int32_t terminator_head, terminator_tail;
uint32_t elemlen;
off_t hop;
/* version */
READ_ERRCHECK(fd, & info->version, sizeof(info->version));
info->version = ntohs(info->version);
if (info->version > SIMCLIST_DUMPFORMAT_VERSION) {
errno = EILSEQ;
return -1;
}
/* timestamp.tv_sec and timestamp.tv_usec */
READ_ERRCHECK(fd, & info->timestamp.tv_sec, sizeof(info->timestamp.tv_sec));
info->timestamp.tv_sec = ntohl(info->timestamp.tv_sec);
READ_ERRCHECK(fd, & info->timestamp.tv_usec, sizeof(info->timestamp.tv_usec));
info->timestamp.tv_usec = ntohl(info->timestamp.tv_usec);
/* list terminator (to check thereafter) */
READ_ERRCHECK(fd, & terminator_head, sizeof(terminator_head));
terminator_head = ntohl(terminator_head);
/* list size */
READ_ERRCHECK(fd, & info->list_size, sizeof(info->list_size));
info->list_size = ntohl(info->list_size);
/* number of elements */
READ_ERRCHECK(fd, & info->list_numels, sizeof(info->list_numels));
info->list_numels = ntohl(info->list_numels);
/* length of each element (for checking for consistency) */
READ_ERRCHECK(fd, & elemlen, sizeof(elemlen));
elemlen = ntohl(elemlen);
/* list hash */
READ_ERRCHECK(fd, & info->list_hash, sizeof(info->list_hash));
info->list_hash = ntohl(info->list_hash);
/* check consistency */
if (elemlen > 0) {
/* constant length, hop by size only */
hop = info->list_size;
} else {
/* non-constant length, hop by size + all element length blocks */
hop = info->list_size + elemlen*info->list_numels;
}
if (lseek(fd, hop, SEEK_CUR) == -1) {
return -1;
}
/* read the trailing value and compare with terminator_head */
READ_ERRCHECK(fd, & terminator_tail, sizeof(terminator_tail));
terminator_tail = ntohl(terminator_tail);
if (terminator_head == terminator_tail)
info->consistent = 1;
else
info->consistent = 0;
return 0;
}
int list_dump_getinfo_file(const char *restrict filename, list_dump_info_t *restrict info) {
int fd, ret;
fd = open(filename, O_RDONLY, 0);
if (fd < 0) return -1;
ret = list_dump_getinfo_filedescriptor(fd, info);
close(fd);
return ret;
}
int list_dump_filedescriptor(const list_t *restrict l, int fd, size_t *restrict len) {
struct list_entry_s *x;
void *ser_buf;
uint32_t bufsize;
struct timeval timeofday;
struct list_dump_header_s header;
if (l->attrs.meter == NULL && l->attrs.serializer == NULL) {
errno = ENOTTY;
return -1;
}
/**** DUMP FORMAT ****
[ ver timestamp | totlen numels elemlen hash | DATA ]
where DATA can be:
@ for constant-size list (element size is constant; elemlen > 0)
[ elem elem ... elem ]
@ for other lists (element size dictated by element_meter each time; elemlen <= 0)
[ size elem size elem ... size elem ]
all integers are encoded in NETWORK BYTE FORMAT
*****/
/* prepare HEADER */
/* version */
header.ver = htons( SIMCLIST_DUMPFORMAT_VERSION );
/* timestamp */
gettimeofday(&timeofday, NULL);
header.timestamp_sec = htonl(timeofday.tv_sec);
header.timestamp_usec = htonl(timeofday.tv_usec);
header.rndterm = htonl((int32_t)get_random());
/* total list size is postprocessed afterwards */
/* number of elements */
header.numels = htonl(l->numels);
/* include an hash, if possible */
if (l->attrs.hasher != NULL) {
if (htonl(list_hash(l, & header.listhash)) != 0) {
/* could not compute list hash! */
return -1;
}
} else {
header.listhash = htonl(0);
}
header.totlistlen = header.elemlen = 0;
/* leave room for the header at the beginning of the file */
if (lseek(fd, SIMCLIST_DUMPFORMAT_HEADERLEN, SEEK_SET) < 0) {
/* errno set by lseek() */
return -1;
}
/* write CONTENT */
if (l->numels > 0) {
/* SPECULATE that the list has constant element size */
if (l->attrs.serializer != NULL) { /* user user-specified serializer */
/* get preliminary length of serialized element in header.elemlen */
ser_buf = l->attrs.serializer(l->head_sentinel->next->data, & header.elemlen);
free(ser_buf);
/* request custom serialization of each element */
for (x = l->head_sentinel->next; x != l->tail_sentinel; x = x->next) {
ser_buf = l->attrs.serializer(x->data, &bufsize);
header.totlistlen += bufsize;
if (header.elemlen != 0) { /* continue on speculation */
if (header.elemlen != bufsize) {
free(ser_buf);
/* constant element length speculation broken! */
header.elemlen = 0;
header.totlistlen = 0;
x = l->head_sentinel;
if (lseek(fd, SIMCLIST_DUMPFORMAT_HEADERLEN, SEEK_SET) < 0) {
/* errno set by lseek() */
return -1;
}
/* restart from the beginning */
continue;
}
/* speculation confirmed */
WRITE_ERRCHECK(fd, ser_buf, bufsize);
} else { /* speculation found broken */
WRITE_ERRCHECK(fd, & bufsize, sizeof(size_t));
WRITE_ERRCHECK(fd, ser_buf, bufsize);
}
free(ser_buf);
}
} else if (l->attrs.meter != NULL) {
header.elemlen = (uint32_t)l->attrs.meter(l->head_sentinel->next->data);
/* serialize the element straight from its data */
for (x = l->head_sentinel->next; x != l->tail_sentinel; x = x->next) {
bufsize = l->attrs.meter(x->data);
header.totlistlen += bufsize;
if (header.elemlen != 0) {
if (header.elemlen != bufsize) {
/* constant element length speculation broken! */
header.elemlen = 0;
header.totlistlen = 0;
x = l->head_sentinel;
/* restart from the beginning */
continue;
}
WRITE_ERRCHECK(fd, x->data, bufsize);
} else {
WRITE_ERRCHECK(fd, &bufsize, sizeof(size_t));
WRITE_ERRCHECK(fd, x->data, bufsize);
}
}
}
/* adjust endianness */
header.elemlen = htonl(header.elemlen);
header.totlistlen = htonl(header.totlistlen);
}
/* write random terminator */
WRITE_ERRCHECK(fd, & header.rndterm, sizeof(header.rndterm)); /* list terminator */
/* write header */
lseek(fd, 0, SEEK_SET);
WRITE_ERRCHECK(fd, & header.ver, sizeof(header.ver)); /* version */
WRITE_ERRCHECK(fd, & header.timestamp_sec, sizeof(header.timestamp_sec)); /* timestamp seconds */
WRITE_ERRCHECK(fd, & header.timestamp_usec, sizeof(header.timestamp_usec)); /* timestamp microseconds */
WRITE_ERRCHECK(fd, & header.rndterm, sizeof(header.rndterm)); /* random terminator */
WRITE_ERRCHECK(fd, & header.totlistlen, sizeof(header.totlistlen)); /* total length of elements */
WRITE_ERRCHECK(fd, & header.numels, sizeof(header.numels)); /* number of elements */
WRITE_ERRCHECK(fd, & header.elemlen, sizeof(header.elemlen)); /* size of each element, or 0 for independent */
WRITE_ERRCHECK(fd, & header.listhash, sizeof(header.listhash)); /* list hash, or 0 for "ignore" */
/* possibly store total written length in "len" */
if (len != NULL) {
*len = sizeof(header) + ntohl(header.totlistlen);
}
return 0;
}
int list_restore_filedescriptor(list_t *restrict l, int fd, size_t *restrict len) {
struct list_dump_header_s header;
unsigned long cnt;
void *buf;
uint32_t elsize, totreadlen, totmemorylen;
memset(& header, 0, sizeof(header));
/* read header */
/* version */
READ_ERRCHECK(fd, &header.ver, sizeof(header.ver));
header.ver = ntohs(header.ver);
if (header.ver != SIMCLIST_DUMPFORMAT_VERSION) {
errno = EILSEQ;
return -1;
}
/* timestamp */
READ_ERRCHECK(fd, & header.timestamp_sec, sizeof(header.timestamp_sec));
header.timestamp_sec = ntohl(header.timestamp_sec);
READ_ERRCHECK(fd, & header.timestamp_usec, sizeof(header.timestamp_usec));
header.timestamp_usec = ntohl(header.timestamp_usec);
/* list terminator */
READ_ERRCHECK(fd, & header.rndterm, sizeof(header.rndterm));
header.rndterm = ntohl(header.rndterm);
/* total list size */
READ_ERRCHECK(fd, & header.totlistlen, sizeof(header.totlistlen));
header.totlistlen = ntohl(header.totlistlen);
/* number of elements */
READ_ERRCHECK(fd, & header.numels, sizeof(header.numels));
header.numels = ntohl(header.numels);
/* length of every element, or '0' = variable */
READ_ERRCHECK(fd, & header.elemlen, sizeof(header.elemlen));
header.elemlen = ntohl(header.elemlen);
/* list hash, or 0 = 'ignore' */
READ_ERRCHECK(fd, & header.listhash, sizeof(header.listhash));
header.listhash = ntohl(header.listhash);
/* read content */
totreadlen = totmemorylen = 0;
if (header.elemlen > 0) {
/* elements have constant size = header.elemlen */
if (l->attrs.unserializer != NULL) {
/* use unserializer */
buf = malloc(header.elemlen);
if (NULL == buf)
return -1;
for (cnt = 0; cnt < header.numels; cnt++) {
READ_ERRCHECK(fd, buf, header.elemlen);
list_append(l, l->attrs.unserializer(buf, & elsize));
totmemorylen += elsize;
}
} else {
/* copy verbatim into memory */
for (cnt = 0; cnt < header.numels; cnt++) {
buf = malloc(header.elemlen);
if (NULL == buf)
return -1;
READ_ERRCHECK(fd, buf, header.elemlen);
list_append(l, buf);
}
totmemorylen = header.numels * header.elemlen;
}
totreadlen = header.numels * header.elemlen;
} else {
/* elements have variable size. Each element is preceded by its size */
if (l->attrs.unserializer != NULL) {
/* use unserializer */
for (cnt = 0; cnt < header.numels; cnt++) {
READ_ERRCHECK(fd, & elsize, sizeof(elsize));
buf = malloc((size_t)elsize);
if (NULL == buf)
return -1;
READ_ERRCHECK(fd, buf, elsize);
totreadlen += elsize;
list_append(l, l->attrs.unserializer(buf, & elsize));
totmemorylen += elsize;
}
} else {
/* copy verbatim into memory */
for (cnt = 0; cnt < header.numels; cnt++) {
READ_ERRCHECK(fd, & elsize, sizeof(elsize));
buf = malloc(elsize);
if (NULL == buf)
return -1;
READ_ERRCHECK(fd, buf, elsize);
totreadlen += elsize;
list_append(l, buf);
}
totmemorylen = totreadlen;
}
}
READ_ERRCHECK(fd, &elsize, sizeof(elsize)); /* read list terminator */
elsize = ntohl(elsize);
/* possibly verify the list consistency */
/* wrt hash */
/* don't do that
if (header.listhash != 0 && header.listhash != list_hash(l)) {
errno = ECANCELED;
return -1;
}
*/
/* wrt header */
if (totreadlen != header.totlistlen && (int32_t)elsize == header.rndterm) {
errno = EPROTO;
return -1;
}
/* wrt file */
if (lseek(fd, 0, SEEK_CUR) != lseek(fd, 0, SEEK_END)) {
errno = EPROTO;
return -1;
}
if (len != NULL) {
*len = totmemorylen;
}
return 0;
}
int list_dump_file(const list_t *restrict l, const char *restrict filename, size_t *restrict len) {
int fd, oflag, mode;
#ifndef _WIN32
oflag = O_RDWR | O_CREAT | O_TRUNC;
mode = S_IRUSR | S_IWUSR | S_IRGRP | S_IROTH;
#else
oflag = _O_RDWR | _O_CREAT | _O_TRUNC;
mode = _S_IRUSR | _S_IWUSR | _S_IRGRP | _S_IROTH;
#endif
fd = open(filename, oflag, mode);
if (fd < 0) return -1;
list_dump_filedescriptor(l, fd, len);
close(fd);
return 0;
}
int list_restore_file(list_t *restrict l, const char *restrict filename, size_t *restrict len) {
int fd;
fd = open(filename, O_RDONLY, 0);
if (fd < 0) return -1;
list_restore_filedescriptor(l, fd, len);
close(fd);
return 0;
}
#endif /* ifndef SIMCLIST_NO_DUMPRESTORE */
static int list_drop_elem(list_t *restrict l, struct list_entry_s *tmp, unsigned int pos) {
if (tmp == NULL) return -1;
/* fix mid pointer. This is wrt the PRE situation */
if (l->numels % 2) { /* now odd */
/* sort out the base case by hand */
if (l->numels == 1) l->mid = NULL;
else if (pos >= l->numels/2) l->mid = l->mid->prev;
} else { /* now even */
if (pos < l->numels/2) l->mid = l->mid->next;
}
tmp->prev->next = tmp->next;
tmp->next->prev = tmp->prev;
/* free what's to be freed */
if (l->attrs.copy_data && tmp->data != NULL)
free(tmp->data);
if (l->spareels != NULL && l->spareelsnum < SIMCLIST_MAX_SPARE_ELEMS) {
l->spareels[l->spareelsnum++] = tmp;
} else {
free(tmp);
}
return 0;
}
/* ready-made comparators and meters */
#define SIMCLIST_NUMBER_COMPARATOR(type) int list_comparator_##type(const void *a, const void *b) { return( *(type *)a < *(type *)b) - (*(type *)a > *(type *)b); }
SIMCLIST_NUMBER_COMPARATOR(int8_t)
SIMCLIST_NUMBER_COMPARATOR(int16_t)
SIMCLIST_NUMBER_COMPARATOR(int32_t)
SIMCLIST_NUMBER_COMPARATOR(int64_t)
SIMCLIST_NUMBER_COMPARATOR(uint8_t)
SIMCLIST_NUMBER_COMPARATOR(uint16_t)
SIMCLIST_NUMBER_COMPARATOR(uint32_t)
SIMCLIST_NUMBER_COMPARATOR(uint64_t)
SIMCLIST_NUMBER_COMPARATOR(float)
SIMCLIST_NUMBER_COMPARATOR(double)
int list_comparator_string(const void *a, const void *b) { return strcmp((const char *)b, (const char *)a); }
/* ready-made metric functions */
#define SIMCLIST_METER(type) size_t list_meter_##type(const void *el) { if (el) { /* kill compiler whinge */ } return sizeof(type); }
SIMCLIST_METER(int8_t)
SIMCLIST_METER(int16_t)
SIMCLIST_METER(int32_t)
SIMCLIST_METER(int64_t)
SIMCLIST_METER(uint8_t)
SIMCLIST_METER(uint16_t)
SIMCLIST_METER(uint32_t)
SIMCLIST_METER(uint64_t)
SIMCLIST_METER(float)
SIMCLIST_METER(double)
size_t list_meter_string(const void *el) { return strlen((const char *)el) + 1; }
/* ready-made hashing functions */
#define SIMCLIST_HASHCOMPUTER(type) list_hash_t list_hashcomputer_##type(const void *el) { return (list_hash_t)(*(type *)el); }
SIMCLIST_HASHCOMPUTER(int8_t)
SIMCLIST_HASHCOMPUTER(int16_t)
SIMCLIST_HASHCOMPUTER(int32_t)
SIMCLIST_HASHCOMPUTER(int64_t)
SIMCLIST_HASHCOMPUTER(uint8_t)
SIMCLIST_HASHCOMPUTER(uint16_t)
SIMCLIST_HASHCOMPUTER(uint32_t)
SIMCLIST_HASHCOMPUTER(uint64_t)
SIMCLIST_HASHCOMPUTER(float)
SIMCLIST_HASHCOMPUTER(double)
list_hash_t list_hashcomputer_string(const void *el) {
size_t l;
list_hash_t hash = 123;
const char *str = (const char *)el;
char plus;
for (l = 0; str[l] != '\0'; l++) {
if (l) plus = hash ^ str[l];
else plus = hash ^ (str[l] - str[0]);
hash += (plus << (CHAR_BIT * (l % sizeof(list_hash_t))));
}
return hash;
}
#ifndef NDEBUG
static int list_repOk(const list_t *restrict l) {
int ok, i;
struct list_entry_s *s;
ok = (l != NULL) && (
/* head/tail checks */
(l->head_sentinel != NULL && l->tail_sentinel != NULL) &&
(l->head_sentinel != l->tail_sentinel) && (l->head_sentinel->prev == NULL && l->tail_sentinel->next == NULL) &&
/* empty list */
(l->numels > 0 || (l->mid == NULL && l->head_sentinel->next == l->tail_sentinel && l->tail_sentinel->prev == l->head_sentinel)) &&
/* spare elements checks */
l->spareelsnum <= SIMCLIST_MAX_SPARE_ELEMS
);
if (!ok) return 0;
if (l->numels >= 1) {
/* correct referencing */
for (i = -1, s = l->head_sentinel; i < (int)(l->numels-1)/2 && s->next != NULL; i++, s = s->next) {
if (s->next->prev != s) break;
}
ok = (i == (int)(l->numels-1)/2 && l->mid == s);
if (!ok) return 0;
for (; s->next != NULL; i++, s = s->next) {
if (s->next->prev != s) break;
}
ok = (i == (int)l->numels && s == l->tail_sentinel);
}
return ok;
}
static int list_attrOk(const list_t *restrict l) {
int ok;
ok = (l->attrs.copy_data == 0 || l->attrs.meter != NULL);
return ok;
}
#endif