git/commit.c
Tilman Sauerbeck 55c3eb434a Indentation fix.
Signed-off-by: Tilman Sauerbeck <tilman@code-monkey.de>
Signed-off-by: Junio C Hamano <junkio@cox.net>
2006-08-17 14:24:54 -07:00

1001 lines
22 KiB
C

#include "cache.h"
#include "tag.h"
#include "commit.h"
int save_commit_buffer = 1;
struct sort_node
{
/*
* the number of children of the associated commit
* that also occur in the list being sorted.
*/
unsigned int indegree;
/*
* reference to original list item that we will re-use
* on output.
*/
struct commit_list * list_item;
};
const char *commit_type = "commit";
struct cmt_fmt_map {
const char *n;
size_t cmp_len;
enum cmit_fmt v;
} cmt_fmts[] = {
{ "raw", 1, CMIT_FMT_RAW },
{ "medium", 1, CMIT_FMT_MEDIUM },
{ "short", 1, CMIT_FMT_SHORT },
{ "email", 1, CMIT_FMT_EMAIL },
{ "full", 5, CMIT_FMT_FULL },
{ "fuller", 5, CMIT_FMT_FULLER },
{ "oneline", 1, CMIT_FMT_ONELINE },
};
enum cmit_fmt get_commit_format(const char *arg)
{
int i;
if (!arg || !*arg)
return CMIT_FMT_DEFAULT;
if (*arg == '=')
arg++;
for (i = 0; i < ARRAY_SIZE(cmt_fmts); i++) {
if (!strncmp(arg, cmt_fmts[i].n, cmt_fmts[i].cmp_len))
return cmt_fmts[i].v;
}
die("invalid --pretty format: %s", arg);
}
static struct commit *check_commit(struct object *obj,
const unsigned char *sha1,
int quiet)
{
if (obj->type != OBJ_COMMIT) {
if (!quiet)
error("Object %s is a %s, not a commit",
sha1_to_hex(sha1), typename(obj->type));
return NULL;
}
return (struct commit *) obj;
}
struct commit *lookup_commit_reference_gently(const unsigned char *sha1,
int quiet)
{
struct object *obj = deref_tag(parse_object(sha1), NULL, 0);
if (!obj)
return NULL;
return check_commit(obj, sha1, quiet);
}
struct commit *lookup_commit_reference(const unsigned char *sha1)
{
return lookup_commit_reference_gently(sha1, 0);
}
struct commit *lookup_commit(const unsigned char *sha1)
{
struct object *obj = lookup_object(sha1);
if (!obj) {
struct commit *ret = alloc_commit_node();
created_object(sha1, &ret->object);
ret->object.type = OBJ_COMMIT;
return ret;
}
if (!obj->type)
obj->type = OBJ_COMMIT;
return check_commit(obj, sha1, 0);
}
static unsigned long parse_commit_date(const char *buf)
{
unsigned long date;
if (memcmp(buf, "author", 6))
return 0;
while (*buf++ != '\n')
/* nada */;
if (memcmp(buf, "committer", 9))
return 0;
while (*buf++ != '>')
/* nada */;
date = strtoul(buf, NULL, 10);
if (date == ULONG_MAX)
date = 0;
return date;
}
static struct commit_graft **commit_graft;
static int commit_graft_alloc, commit_graft_nr;
static int commit_graft_pos(const unsigned char *sha1)
{
int lo, hi;
lo = 0;
hi = commit_graft_nr;
while (lo < hi) {
int mi = (lo + hi) / 2;
struct commit_graft *graft = commit_graft[mi];
int cmp = hashcmp(sha1, graft->sha1);
if (!cmp)
return mi;
if (cmp < 0)
hi = mi;
else
lo = mi + 1;
}
return -lo - 1;
}
int register_commit_graft(struct commit_graft *graft, int ignore_dups)
{
int pos = commit_graft_pos(graft->sha1);
if (0 <= pos) {
if (ignore_dups)
free(graft);
else {
free(commit_graft[pos]);
commit_graft[pos] = graft;
}
return 1;
}
pos = -pos - 1;
if (commit_graft_alloc <= ++commit_graft_nr) {
commit_graft_alloc = alloc_nr(commit_graft_alloc);
commit_graft = xrealloc(commit_graft,
sizeof(*commit_graft) *
commit_graft_alloc);
}
if (pos < commit_graft_nr)
memmove(commit_graft + pos + 1,
commit_graft + pos,
(commit_graft_nr - pos - 1) *
sizeof(*commit_graft));
commit_graft[pos] = graft;
return 0;
}
struct commit_graft *read_graft_line(char *buf, int len)
{
/* The format is just "Commit Parent1 Parent2 ...\n" */
int i;
struct commit_graft *graft = NULL;
if (buf[len-1] == '\n')
buf[--len] = 0;
if (buf[0] == '#' || buf[0] == '\0')
return NULL;
if ((len + 1) % 41) {
bad_graft_data:
error("bad graft data: %s", buf);
free(graft);
return NULL;
}
i = (len + 1) / 41 - 1;
graft = xmalloc(sizeof(*graft) + 20 * i);
graft->nr_parent = i;
if (get_sha1_hex(buf, graft->sha1))
goto bad_graft_data;
for (i = 40; i < len; i += 41) {
if (buf[i] != ' ')
goto bad_graft_data;
if (get_sha1_hex(buf + i + 1, graft->parent[i/41]))
goto bad_graft_data;
}
return graft;
}
int read_graft_file(const char *graft_file)
{
FILE *fp = fopen(graft_file, "r");
char buf[1024];
if (!fp)
return -1;
while (fgets(buf, sizeof(buf), fp)) {
/* The format is just "Commit Parent1 Parent2 ...\n" */
int len = strlen(buf);
struct commit_graft *graft = read_graft_line(buf, len);
if (!graft)
continue;
if (register_commit_graft(graft, 1))
error("duplicate graft data: %s", buf);
}
fclose(fp);
return 0;
}
static void prepare_commit_graft(void)
{
static int commit_graft_prepared;
char *graft_file;
if (commit_graft_prepared)
return;
graft_file = get_graft_file();
read_graft_file(graft_file);
commit_graft_prepared = 1;
}
static struct commit_graft *lookup_commit_graft(const unsigned char *sha1)
{
int pos;
prepare_commit_graft();
pos = commit_graft_pos(sha1);
if (pos < 0)
return NULL;
return commit_graft[pos];
}
int parse_commit_buffer(struct commit *item, void *buffer, unsigned long size)
{
char *tail = buffer;
char *bufptr = buffer;
unsigned char parent[20];
struct commit_list **pptr;
struct commit_graft *graft;
unsigned n_refs = 0;
if (item->object.parsed)
return 0;
item->object.parsed = 1;
tail += size;
if (tail <= bufptr + 5 || memcmp(bufptr, "tree ", 5))
return error("bogus commit object %s", sha1_to_hex(item->object.sha1));
if (tail <= bufptr + 45 || get_sha1_hex(bufptr + 5, parent) < 0)
return error("bad tree pointer in commit %s",
sha1_to_hex(item->object.sha1));
item->tree = lookup_tree(parent);
if (item->tree)
n_refs++;
bufptr += 46; /* "tree " + "hex sha1" + "\n" */
pptr = &item->parents;
graft = lookup_commit_graft(item->object.sha1);
while (bufptr + 48 < tail && !memcmp(bufptr, "parent ", 7)) {
struct commit *new_parent;
if (tail <= bufptr + 48 ||
get_sha1_hex(bufptr + 7, parent) ||
bufptr[47] != '\n')
return error("bad parents in commit %s", sha1_to_hex(item->object.sha1));
bufptr += 48;
if (graft)
continue;
new_parent = lookup_commit(parent);
if (new_parent) {
pptr = &commit_list_insert(new_parent, pptr)->next;
n_refs++;
}
}
if (graft) {
int i;
struct commit *new_parent;
for (i = 0; i < graft->nr_parent; i++) {
new_parent = lookup_commit(graft->parent[i]);
if (!new_parent)
continue;
pptr = &commit_list_insert(new_parent, pptr)->next;
n_refs++;
}
}
item->date = parse_commit_date(bufptr);
if (track_object_refs) {
unsigned i = 0;
struct commit_list *p;
struct object_refs *refs = alloc_object_refs(n_refs);
if (item->tree)
refs->ref[i++] = &item->tree->object;
for (p = item->parents; p; p = p->next)
refs->ref[i++] = &p->item->object;
set_object_refs(&item->object, refs);
}
return 0;
}
int parse_commit(struct commit *item)
{
char type[20];
void *buffer;
unsigned long size;
int ret;
if (item->object.parsed)
return 0;
buffer = read_sha1_file(item->object.sha1, type, &size);
if (!buffer)
return error("Could not read %s",
sha1_to_hex(item->object.sha1));
if (strcmp(type, commit_type)) {
free(buffer);
return error("Object %s not a commit",
sha1_to_hex(item->object.sha1));
}
ret = parse_commit_buffer(item, buffer, size);
if (save_commit_buffer && !ret) {
item->buffer = buffer;
return 0;
}
free(buffer);
return ret;
}
struct commit_list *commit_list_insert(struct commit *item, struct commit_list **list_p)
{
struct commit_list *new_list = xmalloc(sizeof(struct commit_list));
new_list->item = item;
new_list->next = *list_p;
*list_p = new_list;
return new_list;
}
void free_commit_list(struct commit_list *list)
{
while (list) {
struct commit_list *temp = list;
list = temp->next;
free(temp);
}
}
struct commit_list * insert_by_date(struct commit *item, struct commit_list **list)
{
struct commit_list **pp = list;
struct commit_list *p;
while ((p = *pp) != NULL) {
if (p->item->date < item->date) {
break;
}
pp = &p->next;
}
return commit_list_insert(item, pp);
}
void sort_by_date(struct commit_list **list)
{
struct commit_list *ret = NULL;
while (*list) {
insert_by_date((*list)->item, &ret);
*list = (*list)->next;
}
*list = ret;
}
struct commit *pop_most_recent_commit(struct commit_list **list,
unsigned int mark)
{
struct commit *ret = (*list)->item;
struct commit_list *parents = ret->parents;
struct commit_list *old = *list;
*list = (*list)->next;
free(old);
while (parents) {
struct commit *commit = parents->item;
parse_commit(commit);
if (!(commit->object.flags & mark)) {
commit->object.flags |= mark;
insert_by_date(commit, list);
}
parents = parents->next;
}
return ret;
}
void clear_commit_marks(struct commit *commit, unsigned int mark)
{
struct commit_list *parents;
commit->object.flags &= ~mark;
parents = commit->parents;
while (parents) {
struct commit *parent = parents->item;
/* Have we already cleared this? */
if (mark & parent->object.flags)
clear_commit_marks(parent, mark);
parents = parents->next;
}
}
/*
* Generic support for pretty-printing the header
*/
static int get_one_line(const char *msg, unsigned long len)
{
int ret = 0;
while (len--) {
char c = *msg++;
if (!c)
break;
ret++;
if (c == '\n')
break;
}
return ret;
}
static int is_rfc2047_special(char ch)
{
return ((ch & 0x80) || (ch == '=') || (ch == '?') || (ch == '_'));
}
static int add_rfc2047(char *buf, const char *line, int len)
{
char *bp = buf;
int i, needquote;
static const char q_utf8[] = "=?utf-8?q?";
for (i = needquote = 0; !needquote && i < len; i++) {
unsigned ch = line[i];
if (ch & 0x80)
needquote++;
if ((i + 1 < len) &&
(ch == '=' && line[i+1] == '?'))
needquote++;
}
if (!needquote)
return sprintf(buf, "%.*s", len, line);
memcpy(bp, q_utf8, sizeof(q_utf8)-1);
bp += sizeof(q_utf8)-1;
for (i = 0; i < len; i++) {
unsigned ch = line[i] & 0xFF;
if (is_rfc2047_special(ch)) {
sprintf(bp, "=%02X", ch);
bp += 3;
}
else if (ch == ' ')
*bp++ = '_';
else
*bp++ = ch;
}
memcpy(bp, "?=", 2);
bp += 2;
return bp - buf;
}
static int add_user_info(const char *what, enum cmit_fmt fmt, char *buf, const char *line)
{
char *date;
int namelen;
unsigned long time;
int tz, ret;
const char *filler = " ";
if (fmt == CMIT_FMT_ONELINE)
return 0;
date = strchr(line, '>');
if (!date)
return 0;
namelen = ++date - line;
time = strtoul(date, &date, 10);
tz = strtol(date, NULL, 10);
if (fmt == CMIT_FMT_EMAIL) {
char *name_tail = strchr(line, '<');
int display_name_length;
if (!name_tail)
return 0;
while (line < name_tail && isspace(name_tail[-1]))
name_tail--;
display_name_length = name_tail - line;
filler = "";
strcpy(buf, "From: ");
ret = strlen(buf);
ret += add_rfc2047(buf + ret, line, display_name_length);
memcpy(buf + ret, name_tail, namelen - display_name_length);
ret += namelen - display_name_length;
buf[ret++] = '\n';
}
else {
ret = sprintf(buf, "%s: %.*s%.*s\n", what,
(fmt == CMIT_FMT_FULLER) ? 4 : 0,
filler, namelen, line);
}
switch (fmt) {
case CMIT_FMT_MEDIUM:
ret += sprintf(buf + ret, "Date: %s\n", show_date(time, tz));
break;
case CMIT_FMT_EMAIL:
ret += sprintf(buf + ret, "Date: %s\n",
show_rfc2822_date(time, tz));
break;
case CMIT_FMT_FULLER:
ret += sprintf(buf + ret, "%sDate: %s\n", what, show_date(time, tz));
break;
default:
/* notin' */
break;
}
return ret;
}
static int is_empty_line(const char *line, int *len_p)
{
int len = *len_p;
while (len && isspace(line[len-1]))
len--;
*len_p = len;
return !len;
}
static int add_merge_info(enum cmit_fmt fmt, char *buf, const struct commit *commit, int abbrev)
{
struct commit_list *parent = commit->parents;
int offset;
if ((fmt == CMIT_FMT_ONELINE) || (fmt == CMIT_FMT_EMAIL) ||
!parent || !parent->next)
return 0;
offset = sprintf(buf, "Merge:");
while (parent) {
struct commit *p = parent->item;
const char *hex = abbrev
? find_unique_abbrev(p->object.sha1, abbrev)
: sha1_to_hex(p->object.sha1);
const char *dots = (abbrev && strlen(hex) != 40) ? "..." : "";
parent = parent->next;
offset += sprintf(buf + offset, " %s%s", hex, dots);
}
buf[offset++] = '\n';
return offset;
}
unsigned long pretty_print_commit(enum cmit_fmt fmt, const struct commit *commit, unsigned long len, char *buf, unsigned long space, int abbrev, const char *subject, const char *after_subject)
{
int hdr = 1, body = 0;
unsigned long offset = 0;
int indent = 4;
int parents_shown = 0;
const char *msg = commit->buffer;
int plain_non_ascii = 0;
if (fmt == CMIT_FMT_ONELINE || fmt == CMIT_FMT_EMAIL)
indent = 0;
/* After-subject is used to pass in Content-Type: multipart
* MIME header; in that case we do not have to do the
* plaintext content type even if the commit message has
* non 7-bit ASCII character. Otherwise, check if we need
* to say this is not a 7-bit ASCII.
*/
if (fmt == CMIT_FMT_EMAIL && !after_subject) {
int i, ch, in_body;
for (in_body = i = 0; (ch = msg[i]) && i < len; i++) {
if (!in_body) {
/* author could be non 7-bit ASCII but
* the log may so; skip over the
* header part first.
*/
if (ch == '\n' &&
i + 1 < len && msg[i+1] == '\n')
in_body = 1;
}
else if (ch & 0x80) {
plain_non_ascii = 1;
break;
}
}
}
for (;;) {
const char *line = msg;
int linelen = get_one_line(msg, len);
if (!linelen)
break;
/*
* We want some slop for indentation and a possible
* final "...". Thus the "+ 20".
*/
if (offset + linelen + 20 > space) {
memcpy(buf + offset, " ...\n", 8);
offset += 8;
break;
}
msg += linelen;
len -= linelen;
if (hdr) {
if (linelen == 1) {
hdr = 0;
if ((fmt != CMIT_FMT_ONELINE) && !subject)
buf[offset++] = '\n';
continue;
}
if (fmt == CMIT_FMT_RAW) {
memcpy(buf + offset, line, linelen);
offset += linelen;
continue;
}
if (!memcmp(line, "parent ", 7)) {
if (linelen != 48)
die("bad parent line in commit");
continue;
}
if (!parents_shown) {
offset += add_merge_info(fmt, buf + offset,
commit, abbrev);
parents_shown = 1;
continue;
}
/*
* MEDIUM == DEFAULT shows only author with dates.
* FULL shows both authors but not dates.
* FULLER shows both authors and dates.
*/
if (!memcmp(line, "author ", 7))
offset += add_user_info("Author", fmt,
buf + offset,
line + 7);
if (!memcmp(line, "committer ", 10) &&
(fmt == CMIT_FMT_FULL || fmt == CMIT_FMT_FULLER))
offset += add_user_info("Commit", fmt,
buf + offset,
line + 10);
continue;
}
if (!subject)
body = 1;
if (is_empty_line(line, &linelen)) {
if (!body)
continue;
if (subject)
continue;
if (fmt == CMIT_FMT_SHORT)
break;
}
if (subject) {
int slen = strlen(subject);
memcpy(buf + offset, subject, slen);
offset += slen;
offset += add_rfc2047(buf + offset, line, linelen);
}
else {
memset(buf + offset, ' ', indent);
memcpy(buf + offset + indent, line, linelen);
offset += linelen + indent;
}
buf[offset++] = '\n';
if (fmt == CMIT_FMT_ONELINE)
break;
if (subject && plain_non_ascii) {
static const char header[] =
"Content-Type: text/plain; charset=UTF-8\n"
"Content-Transfer-Encoding: 8bit\n";
memcpy(buf + offset, header, sizeof(header)-1);
offset += sizeof(header)-1;
}
if (after_subject) {
int slen = strlen(after_subject);
if (slen > space - offset - 1)
slen = space - offset - 1;
memcpy(buf + offset, after_subject, slen);
offset += slen;
after_subject = NULL;
}
subject = NULL;
}
while (offset && isspace(buf[offset-1]))
offset--;
/* Make sure there is an EOLN for the non-oneline case */
if (fmt != CMIT_FMT_ONELINE)
buf[offset++] = '\n';
/*
* make sure there is another EOLN to separate the headers from whatever
* body the caller appends if we haven't already written a body
*/
if (fmt == CMIT_FMT_EMAIL && !body)
buf[offset++] = '\n';
buf[offset] = '\0';
return offset;
}
struct commit *pop_commit(struct commit_list **stack)
{
struct commit_list *top = *stack;
struct commit *item = top ? top->item : NULL;
if (top) {
*stack = top->next;
free(top);
}
return item;
}
int count_parents(struct commit * commit)
{
int count;
struct commit_list * parents = commit->parents;
for (count = 0; parents; parents = parents->next,count++)
;
return count;
}
void topo_sort_default_setter(struct commit *c, void *data)
{
c->util = data;
}
void *topo_sort_default_getter(struct commit *c)
{
return c->util;
}
/*
* Performs an in-place topological sort on the list supplied.
*/
void sort_in_topological_order(struct commit_list ** list, int lifo)
{
sort_in_topological_order_fn(list, lifo, topo_sort_default_setter,
topo_sort_default_getter);
}
void sort_in_topological_order_fn(struct commit_list ** list, int lifo,
topo_sort_set_fn_t setter,
topo_sort_get_fn_t getter)
{
struct commit_list * next = *list;
struct commit_list * work = NULL, **insert;
struct commit_list ** pptr = list;
struct sort_node * nodes;
struct sort_node * next_nodes;
int count = 0;
/* determine the size of the list */
while (next) {
next = next->next;
count++;
}
if (!count)
return;
/* allocate an array to help sort the list */
nodes = xcalloc(count, sizeof(*nodes));
/* link the list to the array */
next_nodes = nodes;
next=*list;
while (next) {
next_nodes->list_item = next;
setter(next->item, next_nodes);
next_nodes++;
next = next->next;
}
/* update the indegree */
next=*list;
while (next) {
struct commit_list * parents = next->item->parents;
while (parents) {
struct commit * parent=parents->item;
struct sort_node * pn = (struct sort_node *) getter(parent);
if (pn)
pn->indegree++;
parents=parents->next;
}
next=next->next;
}
/*
* find the tips
*
* tips are nodes not reachable from any other node in the list
*
* the tips serve as a starting set for the work queue.
*/
next=*list;
insert = &work;
while (next) {
struct sort_node * node = (struct sort_node *) getter(next->item);
if (node->indegree == 0) {
insert = &commit_list_insert(next->item, insert)->next;
}
next=next->next;
}
/* process the list in topological order */
if (!lifo)
sort_by_date(&work);
while (work) {
struct commit * work_item = pop_commit(&work);
struct sort_node * work_node = (struct sort_node *) getter(work_item);
struct commit_list * parents = work_item->parents;
while (parents) {
struct commit * parent=parents->item;
struct sort_node * pn = (struct sort_node *) getter(parent);
if (pn) {
/*
* parents are only enqueued for emission
* when all their children have been emitted thereby
* guaranteeing topological order.
*/
pn->indegree--;
if (!pn->indegree) {
if (!lifo)
insert_by_date(parent, &work);
else
commit_list_insert(parent, &work);
}
}
parents=parents->next;
}
/*
* work_item is a commit all of whose children
* have already been emitted. we can emit it now.
*/
*pptr = work_node->list_item;
pptr = &(*pptr)->next;
*pptr = NULL;
setter(work_item, NULL);
}
free(nodes);
}
/* merge-rebase stuff */
/* bits #0..7 in revision.h */
#define PARENT1 (1u<< 8)
#define PARENT2 (1u<< 9)
#define STALE (1u<<10)
#define RESULT (1u<<11)
static struct commit *interesting(struct commit_list *list)
{
while (list) {
struct commit *commit = list->item;
list = list->next;
if (commit->object.flags & STALE)
continue;
return commit;
}
return NULL;
}
static struct commit_list *merge_bases(struct commit *one, struct commit *two)
{
struct commit_list *list = NULL;
struct commit_list *result = NULL;
if (one == two)
/* We do not mark this even with RESULT so we do not
* have to clean it up.
*/
return commit_list_insert(one, &result);
parse_commit(one);
parse_commit(two);
one->object.flags |= PARENT1;
two->object.flags |= PARENT2;
insert_by_date(one, &list);
insert_by_date(two, &list);
while (interesting(list)) {
struct commit *commit;
struct commit_list *parents;
struct commit_list *n;
int flags;
commit = list->item;
n = list->next;
free(list);
list = n;
flags = commit->object.flags & (PARENT1 | PARENT2 | STALE);
if (flags == (PARENT1 | PARENT2)) {
if (!(commit->object.flags & RESULT)) {
commit->object.flags |= RESULT;
insert_by_date(commit, &result);
}
/* Mark parents of a found merge stale */
flags |= STALE;
}
parents = commit->parents;
while (parents) {
struct commit *p = parents->item;
parents = parents->next;
if ((p->object.flags & flags) == flags)
continue;
parse_commit(p);
p->object.flags |= flags;
insert_by_date(p, &list);
}
}
/* Clean up the result to remove stale ones */
list = result; result = NULL;
while (list) {
struct commit_list *n = list->next;
if (!(list->item->object.flags & STALE))
insert_by_date(list->item, &result);
free(list);
list = n;
}
return result;
}
struct commit_list *get_merge_bases(struct commit *one,
struct commit *two,
int cleanup)
{
const unsigned all_flags = (PARENT1 | PARENT2 | STALE | RESULT);
struct commit_list *list;
struct commit **rslt;
struct commit_list *result;
int cnt, i, j;
result = merge_bases(one, two);
if (one == two)
return result;
if (!result || !result->next) {
if (cleanup) {
clear_commit_marks(one, all_flags);
clear_commit_marks(two, all_flags);
}
return result;
}
/* There are more than one */
cnt = 0;
list = result;
while (list) {
list = list->next;
cnt++;
}
rslt = xcalloc(cnt, sizeof(*rslt));
for (list = result, i = 0; list; list = list->next)
rslt[i++] = list->item;
free_commit_list(result);
clear_commit_marks(one, all_flags);
clear_commit_marks(two, all_flags);
for (i = 0; i < cnt - 1; i++) {
for (j = i+1; j < cnt; j++) {
if (!rslt[i] || !rslt[j])
continue;
result = merge_bases(rslt[i], rslt[j]);
clear_commit_marks(rslt[i], all_flags);
clear_commit_marks(rslt[j], all_flags);
for (list = result; list; list = list->next) {
if (rslt[i] == list->item)
rslt[i] = NULL;
if (rslt[j] == list->item)
rslt[j] = NULL;
}
}
}
/* Surviving ones in rslt[] are the independent results */
result = NULL;
for (i = 0; i < cnt; i++) {
if (rslt[i])
insert_by_date(rslt[i], &result);
}
free(rslt);
return result;
}