nhyatt/putty-source
1
0
Fork 0
mirror of https://git.tartarus.org/simon/putty.git synced 2025-04-10 15:48:06 -05:00
Code Issues Projects Releases Wiki Activity

Rework bufchain code to allow for variable-sized granules.

Browse Source 
bufchain_add() now allocates at most one new granule.  Granules still 
have a minimum size, so small adds still get coalesced.

The main practical consequence of this is that PSCP and PSFTP now 
generate 4K SSH packets rather than 512-byte ones.  Also, the compiled 
code (on my Ubuntu box) is fractionally smaller.

[originally from svn r9602]
This commit is contained in:
Ben Harris 2012-08-11 09:10:31 +00:00
parent 37ea0f4541
commit b599e77ada
1 changed files with 32 additions and 32 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

64
misc.c
View File

@ -364,12 +364,11 @@ void base64_encode_atom(unsigned char *data, int n, char *out)
* - return the current size of the buffer chain in bytes
*/
#define BUFFER_GRANULE 512
#define BUFFER_MIN_GRANULE 512
struct bufchain_granule {
struct bufchain_granule *next;
int buflen, bufpos;
char buf[BUFFER_GRANULE];
char *bufpos, *bufend, *bufmax;
};
void bufchain_init(bufchain *ch)
@ -403,28 +402,29 @@ void bufchain_add(bufchain *ch, const void *data, int len)
ch->buffersize += len;
if (ch->tail && ch->tail->buflen < BUFFER_GRANULE) {
int copylen = min(len, BUFFER_GRANULE - ch->tail->buflen);
memcpy(ch->tail->buf + ch->tail->buflen, buf, copylen);
buf += copylen;
len -= copylen;
ch->tail->buflen += copylen;
}
while (len > 0) {
int grainlen = min(len, BUFFER_GRANULE);
struct bufchain_granule *newbuf;
newbuf = snew(struct bufchain_granule);
newbuf->bufpos = 0;
newbuf->buflen = grainlen;
memcpy(newbuf->buf, buf, grainlen);
buf += grainlen;
len -= grainlen;
if (ch->tail)
ch->tail->next = newbuf;
else
ch->head = ch->tail = newbuf;
newbuf->next = NULL;
ch->tail = newbuf;
if (ch->tail && ch->tail->bufend < ch->tail->bufmax) {
int copylen = min(len, ch->tail->bufmax - ch->tail->bufend);
memcpy(ch->tail->bufend, buf, copylen);
buf += copylen;
len -= copylen;
ch->tail->bufend += copylen;
}
if (len > 0) {
int grainlen =
max(sizeof(struct bufchain_granule) + len, BUFFER_MIN_GRANULE);
struct bufchain_granule *newbuf;
newbuf = smalloc(grainlen);
newbuf->bufpos = newbuf->bufend =
(char *)newbuf + sizeof(struct bufchain_granule);
newbuf->bufmax = (char *)newbuf + grainlen;
newbuf->next = NULL;
if (ch->tail)
ch->tail->next = newbuf;
else
ch->head = newbuf;
ch->tail = newbuf;
}
}
}
@ -436,13 +436,13 @@ void bufchain_consume(bufchain *ch, int len)
while (len > 0) {
int remlen = len;
assert(ch->head != NULL);
if (remlen >= ch->head->buflen - ch->head->bufpos) {
remlen = ch->head->buflen - ch->head->bufpos;
if (remlen >= ch->head->bufend - ch->head->bufpos) {
remlen = ch->head->bufend - ch->head->bufpos;
tmp = ch->head;
ch->head = tmp->next;
sfree(tmp);
if (!ch->head)
ch->tail = NULL;
sfree(tmp);
} else
ch->head->bufpos += remlen;
ch->buffersize -= remlen;
@ -452,8 +452,8 @@ void bufchain_consume(bufchain *ch, int len)
void bufchain_prefix(bufchain *ch, void **data, int *len)
{
*len = ch->head->buflen - ch->head->bufpos;
*data = ch->head->buf + ch->head->bufpos;
*len = ch->head->bufend - ch->head->bufpos;
*data = ch->head->bufpos;
}
void bufchain_fetch(bufchain *ch, void *data, int len)
@ -468,9 +468,9 @@ void bufchain_fetch(bufchain *ch, void *data, int len)
int remlen = len;
assert(tmp != NULL);
if (remlen >= tmp->buflen - tmp->bufpos)
remlen = tmp->buflen - tmp->bufpos;
memcpy(data_c, tmp->buf + tmp->bufpos, remlen);
if (remlen >= tmp->bufend - tmp->bufpos)
remlen = tmp->bufend - tmp->bufpos;
memcpy(data_c, tmp->bufpos, remlen);
tmp = tmp->next;
len -= remlen;