git/convert.c
Junio C Hamano 87afe9a5ed lf_to_crlf_filter(): tell the caller we added "\n" when draining
This can only happen when the input size is multiple of the
buffer size of the cascade filter (16k) and ends with an LF,
but in such a case, the code forgot to tell the caller that
it added the "\n" it could not add during the last round.

Signed-off-by: Junio C Hamano <gitster@pobox.com>
2011-12-16 14:39:37 -08:00

1239 lines
28 KiB
C

#include "cache.h"
#include "attr.h"
#include "run-command.h"
#include "quote.h"
/*
* convert.c - convert a file when checking it out and checking it in.
*
* This should use the pathname to decide on whether it wants to do some
* more interesting conversions (automatic gzip/unzip, general format
* conversions etc etc), but by default it just does automatic CRLF<->LF
* translation when the "text" attribute or "auto_crlf" option is set.
*/
enum crlf_action {
CRLF_GUESS = -1,
CRLF_BINARY = 0,
CRLF_TEXT,
CRLF_INPUT,
CRLF_CRLF,
CRLF_AUTO
};
struct text_stat {
/* NUL, CR, LF and CRLF counts */
unsigned nul, cr, lf, crlf;
/* These are just approximations! */
unsigned printable, nonprintable;
};
static void gather_stats(const char *buf, unsigned long size, struct text_stat *stats)
{
unsigned long i;
memset(stats, 0, sizeof(*stats));
for (i = 0; i < size; i++) {
unsigned char c = buf[i];
if (c == '\r') {
stats->cr++;
if (i+1 < size && buf[i+1] == '\n')
stats->crlf++;
continue;
}
if (c == '\n') {
stats->lf++;
continue;
}
if (c == 127)
/* DEL */
stats->nonprintable++;
else if (c < 32) {
switch (c) {
/* BS, HT, ESC and FF */
case '\b': case '\t': case '\033': case '\014':
stats->printable++;
break;
case 0:
stats->nul++;
/* fall through */
default:
stats->nonprintable++;
}
}
else
stats->printable++;
}
/* If file ends with EOF then don't count this EOF as non-printable. */
if (size >= 1 && buf[size-1] == '\032')
stats->nonprintable--;
}
/*
* The same heuristics as diff.c::mmfile_is_binary()
*/
static int is_binary(unsigned long size, struct text_stat *stats)
{
if (stats->nul)
return 1;
if ((stats->printable >> 7) < stats->nonprintable)
return 1;
/*
* Other heuristics? Average line length might be relevant,
* as might LF vs CR vs CRLF counts..
*
* NOTE! It might be normal to have a low ratio of CRLF to LF
* (somebody starts with a LF-only file and edits it with an editor
* that adds CRLF only to lines that are added..). But do we
* want to support CR-only? Probably not.
*/
return 0;
}
static enum eol output_eol(enum crlf_action crlf_action)
{
switch (crlf_action) {
case CRLF_BINARY:
return EOL_UNSET;
case CRLF_CRLF:
return EOL_CRLF;
case CRLF_INPUT:
return EOL_LF;
case CRLF_GUESS:
if (!auto_crlf)
return EOL_UNSET;
/* fall through */
case CRLF_TEXT:
case CRLF_AUTO:
if (auto_crlf == AUTO_CRLF_TRUE)
return EOL_CRLF;
else if (auto_crlf == AUTO_CRLF_INPUT)
return EOL_LF;
else if (core_eol == EOL_UNSET)
return EOL_NATIVE;
}
return core_eol;
}
static void check_safe_crlf(const char *path, enum crlf_action crlf_action,
struct text_stat *stats, enum safe_crlf checksafe)
{
if (!checksafe)
return;
if (output_eol(crlf_action) == EOL_LF) {
/*
* CRLFs would not be restored by checkout:
* check if we'd remove CRLFs
*/
if (stats->crlf) {
if (checksafe == SAFE_CRLF_WARN)
warning("CRLF will be replaced by LF in %s.\nThe file will have its original line endings in your working directory.", path);
else /* i.e. SAFE_CRLF_FAIL */
die("CRLF would be replaced by LF in %s.", path);
}
} else if (output_eol(crlf_action) == EOL_CRLF) {
/*
* CRLFs would be added by checkout:
* check if we have "naked" LFs
*/
if (stats->lf != stats->crlf) {
if (checksafe == SAFE_CRLF_WARN)
warning("LF will be replaced by CRLF in %s.\nThe file will have its original line endings in your working directory.", path);
else /* i.e. SAFE_CRLF_FAIL */
die("LF would be replaced by CRLF in %s", path);
}
}
}
static int has_cr_in_index(const char *path)
{
int pos, len;
unsigned long sz;
enum object_type type;
void *data;
int has_cr;
struct index_state *istate = &the_index;
len = strlen(path);
pos = index_name_pos(istate, path, len);
if (pos < 0) {
/*
* We might be in the middle of a merge, in which
* case we would read stage #2 (ours).
*/
int i;
for (i = -pos - 1;
(pos < 0 && i < istate->cache_nr &&
!strcmp(istate->cache[i]->name, path));
i++)
if (ce_stage(istate->cache[i]) == 2)
pos = i;
}
if (pos < 0)
return 0;
data = read_sha1_file(istate->cache[pos]->sha1, &type, &sz);
if (!data || type != OBJ_BLOB) {
free(data);
return 0;
}
has_cr = memchr(data, '\r', sz) != NULL;
free(data);
return has_cr;
}
static int crlf_to_git(const char *path, const char *src, size_t len,
struct strbuf *buf,
enum crlf_action crlf_action, enum safe_crlf checksafe)
{
struct text_stat stats;
char *dst;
if (crlf_action == CRLF_BINARY ||
(crlf_action == CRLF_GUESS && auto_crlf == AUTO_CRLF_FALSE) || !len)
return 0;
gather_stats(src, len, &stats);
if (crlf_action == CRLF_AUTO || crlf_action == CRLF_GUESS) {
/*
* We're currently not going to even try to convert stuff
* that has bare CR characters. Does anybody do that crazy
* stuff?
*/
if (stats.cr != stats.crlf)
return 0;
/*
* And add some heuristics for binary vs text, of course...
*/
if (is_binary(len, &stats))
return 0;
if (crlf_action == CRLF_GUESS) {
/*
* If the file in the index has any CR in it, do not convert.
* This is the new safer autocrlf handling.
*/
if (has_cr_in_index(path))
return 0;
}
}
check_safe_crlf(path, crlf_action, &stats, checksafe);
/* Optimization: No CR? Nothing to convert, regardless. */
if (!stats.cr)
return 0;
/* only grow if not in place */
if (strbuf_avail(buf) + buf->len < len)
strbuf_grow(buf, len - buf->len);
dst = buf->buf;
if (crlf_action == CRLF_AUTO || crlf_action == CRLF_GUESS) {
/*
* If we guessed, we already know we rejected a file with
* lone CR, and we can strip a CR without looking at what
* follow it.
*/
do {
unsigned char c = *src++;
if (c != '\r')
*dst++ = c;
} while (--len);
} else {
do {
unsigned char c = *src++;
if (! (c == '\r' && (1 < len && *src == '\n')))
*dst++ = c;
} while (--len);
}
strbuf_setlen(buf, dst - buf->buf);
return 1;
}
static int crlf_to_worktree(const char *path, const char *src, size_t len,
struct strbuf *buf, enum crlf_action crlf_action)
{
char *to_free = NULL;
struct text_stat stats;
if (!len || output_eol(crlf_action) != EOL_CRLF)
return 0;
gather_stats(src, len, &stats);
/* No LF? Nothing to convert, regardless. */
if (!stats.lf)
return 0;
/* Was it already in CRLF format? */
if (stats.lf == stats.crlf)
return 0;
if (crlf_action == CRLF_AUTO || crlf_action == CRLF_GUESS) {
if (crlf_action == CRLF_GUESS) {
/* If we have any CR or CRLF line endings, we do not touch it */
/* This is the new safer autocrlf-handling */
if (stats.cr > 0 || stats.crlf > 0)
return 0;
}
/* If we have any bare CR characters, we're not going to touch it */
if (stats.cr != stats.crlf)
return 0;
if (is_binary(len, &stats))
return 0;
}
/* are we "faking" in place editing ? */
if (src == buf->buf)
to_free = strbuf_detach(buf, NULL);
strbuf_grow(buf, len + stats.lf - stats.crlf);
for (;;) {
const char *nl = memchr(src, '\n', len);
if (!nl)
break;
if (nl > src && nl[-1] == '\r') {
strbuf_add(buf, src, nl + 1 - src);
} else {
strbuf_add(buf, src, nl - src);
strbuf_addstr(buf, "\r\n");
}
len -= nl + 1 - src;
src = nl + 1;
}
strbuf_add(buf, src, len);
free(to_free);
return 1;
}
struct filter_params {
const char *src;
unsigned long size;
const char *cmd;
const char *path;
};
static int filter_buffer(int in, int out, void *data)
{
/*
* Spawn cmd and feed the buffer contents through its stdin.
*/
struct child_process child_process;
struct filter_params *params = (struct filter_params *)data;
int write_err, status;
const char *argv[] = { NULL, NULL };
/* apply % substitution to cmd */
struct strbuf cmd = STRBUF_INIT;
struct strbuf path = STRBUF_INIT;
struct strbuf_expand_dict_entry dict[] = {
{ "f", NULL, },
{ NULL, NULL, },
};
/* quote the path to preserve spaces, etc. */
sq_quote_buf(&path, params->path);
dict[0].value = path.buf;
/* expand all %f with the quoted path */
strbuf_expand(&cmd, params->cmd, strbuf_expand_dict_cb, &dict);
strbuf_release(&path);
argv[0] = cmd.buf;
memset(&child_process, 0, sizeof(child_process));
child_process.argv = argv;
child_process.use_shell = 1;
child_process.in = -1;
child_process.out = out;
if (start_command(&child_process))
return error("cannot fork to run external filter %s", params->cmd);
write_err = (write_in_full(child_process.in, params->src, params->size) < 0);
if (close(child_process.in))
write_err = 1;
if (write_err)
error("cannot feed the input to external filter %s", params->cmd);
status = finish_command(&child_process);
if (status)
error("external filter %s failed %d", params->cmd, status);
strbuf_release(&cmd);
return (write_err || status);
}
static int apply_filter(const char *path, const char *src, size_t len,
struct strbuf *dst, const char *cmd)
{
/*
* Create a pipeline to have the command filter the buffer's
* contents.
*
* (child --> cmd) --> us
*/
int ret = 1;
struct strbuf nbuf = STRBUF_INIT;
struct async async;
struct filter_params params;
if (!cmd)
return 0;
memset(&async, 0, sizeof(async));
async.proc = filter_buffer;
async.data = &params;
async.out = -1;
params.src = src;
params.size = len;
params.cmd = cmd;
params.path = path;
fflush(NULL);
if (start_async(&async))
return 0; /* error was already reported */
if (strbuf_read(&nbuf, async.out, len) < 0) {
error("read from external filter %s failed", cmd);
ret = 0;
}
if (close(async.out)) {
error("read from external filter %s failed", cmd);
ret = 0;
}
if (finish_async(&async)) {
error("external filter %s failed", cmd);
ret = 0;
}
if (ret) {
strbuf_swap(dst, &nbuf);
}
strbuf_release(&nbuf);
return ret;
}
static struct convert_driver {
const char *name;
struct convert_driver *next;
const char *smudge;
const char *clean;
} *user_convert, **user_convert_tail;
static int read_convert_config(const char *var, const char *value, void *cb)
{
const char *ep, *name;
int namelen;
struct convert_driver *drv;
/*
* External conversion drivers are configured using
* "filter.<name>.variable".
*/
if (prefixcmp(var, "filter.") || (ep = strrchr(var, '.')) == var + 6)
return 0;
name = var + 7;
namelen = ep - name;
for (drv = user_convert; drv; drv = drv->next)
if (!strncmp(drv->name, name, namelen) && !drv->name[namelen])
break;
if (!drv) {
drv = xcalloc(1, sizeof(struct convert_driver));
drv->name = xmemdupz(name, namelen);
*user_convert_tail = drv;
user_convert_tail = &(drv->next);
}
ep++;
/*
* filter.<name>.smudge and filter.<name>.clean specifies
* the command line:
*
* command-line
*
* The command-line will not be interpolated in any way.
*/
if (!strcmp("smudge", ep))
return git_config_string(&drv->smudge, var, value);
if (!strcmp("clean", ep))
return git_config_string(&drv->clean, var, value);
return 0;
}
static int count_ident(const char *cp, unsigned long size)
{
/*
* "$Id: 0000000000000000000000000000000000000000 $" <=> "$Id$"
*/
int cnt = 0;
char ch;
while (size) {
ch = *cp++;
size--;
if (ch != '$')
continue;
if (size < 3)
break;
if (memcmp("Id", cp, 2))
continue;
ch = cp[2];
cp += 3;
size -= 3;
if (ch == '$')
cnt++; /* $Id$ */
if (ch != ':')
continue;
/*
* "$Id: ... "; scan up to the closing dollar sign and discard.
*/
while (size) {
ch = *cp++;
size--;
if (ch == '$') {
cnt++;
break;
}
if (ch == '\n')
break;
}
}
return cnt;
}
static int ident_to_git(const char *path, const char *src, size_t len,
struct strbuf *buf, int ident)
{
char *dst, *dollar;
if (!ident || !count_ident(src, len))
return 0;
/* only grow if not in place */
if (strbuf_avail(buf) + buf->len < len)
strbuf_grow(buf, len - buf->len);
dst = buf->buf;
for (;;) {
dollar = memchr(src, '$', len);
if (!dollar)
break;
memmove(dst, src, dollar + 1 - src);
dst += dollar + 1 - src;
len -= dollar + 1 - src;
src = dollar + 1;
if (len > 3 && !memcmp(src, "Id:", 3)) {
dollar = memchr(src + 3, '$', len - 3);
if (!dollar)
break;
if (memchr(src + 3, '\n', dollar - src - 3)) {
/* Line break before the next dollar. */
continue;
}
memcpy(dst, "Id$", 3);
dst += 3;
len -= dollar + 1 - src;
src = dollar + 1;
}
}
memmove(dst, src, len);
strbuf_setlen(buf, dst + len - buf->buf);
return 1;
}
static int ident_to_worktree(const char *path, const char *src, size_t len,
struct strbuf *buf, int ident)
{
unsigned char sha1[20];
char *to_free = NULL, *dollar, *spc;
int cnt;
if (!ident)
return 0;
cnt = count_ident(src, len);
if (!cnt)
return 0;
/* are we "faking" in place editing ? */
if (src == buf->buf)
to_free = strbuf_detach(buf, NULL);
hash_sha1_file(src, len, "blob", sha1);
strbuf_grow(buf, len + cnt * 43);
for (;;) {
/* step 1: run to the next '$' */
dollar = memchr(src, '$', len);
if (!dollar)
break;
strbuf_add(buf, src, dollar + 1 - src);
len -= dollar + 1 - src;
src = dollar + 1;
/* step 2: does it looks like a bit like Id:xxx$ or Id$ ? */
if (len < 3 || memcmp("Id", src, 2))
continue;
/* step 3: skip over Id$ or Id:xxxxx$ */
if (src[2] == '$') {
src += 3;
len -= 3;
} else if (src[2] == ':') {
/*
* It's possible that an expanded Id has crept its way into the
* repository, we cope with that by stripping the expansion out.
* This is probably not a good idea, since it will cause changes
* on checkout, which won't go away by stash, but let's keep it
* for git-style ids.
*/
dollar = memchr(src + 3, '$', len - 3);
if (!dollar) {
/* incomplete keyword, no more '$', so just quit the loop */
break;
}
if (memchr(src + 3, '\n', dollar - src - 3)) {
/* Line break before the next dollar. */
continue;
}
spc = memchr(src + 4, ' ', dollar - src - 4);
if (spc && spc < dollar-1) {
/* There are spaces in unexpected places.
* This is probably an id from some other
* versioning system. Keep it for now.
*/
continue;
}
len -= dollar + 1 - src;
src = dollar + 1;
} else {
/* it wasn't a "Id$" or "Id:xxxx$" */
continue;
}
/* step 4: substitute */
strbuf_addstr(buf, "Id: ");
strbuf_add(buf, sha1_to_hex(sha1), 40);
strbuf_addstr(buf, " $");
}
strbuf_add(buf, src, len);
free(to_free);
return 1;
}
static int git_path_check_crlf(const char *path, struct git_attr_check *check)
{
const char *value = check->value;
if (ATTR_TRUE(value))
return CRLF_TEXT;
else if (ATTR_FALSE(value))
return CRLF_BINARY;
else if (ATTR_UNSET(value))
;
else if (!strcmp(value, "input"))
return CRLF_INPUT;
else if (!strcmp(value, "auto"))
return CRLF_AUTO;
return CRLF_GUESS;
}
static int git_path_check_eol(const char *path, struct git_attr_check *check)
{
const char *value = check->value;
if (ATTR_UNSET(value))
;
else if (!strcmp(value, "lf"))
return EOL_LF;
else if (!strcmp(value, "crlf"))
return EOL_CRLF;
return EOL_UNSET;
}
static struct convert_driver *git_path_check_convert(const char *path,
struct git_attr_check *check)
{
const char *value = check->value;
struct convert_driver *drv;
if (ATTR_TRUE(value) || ATTR_FALSE(value) || ATTR_UNSET(value))
return NULL;
for (drv = user_convert; drv; drv = drv->next)
if (!strcmp(value, drv->name))
return drv;
return NULL;
}
static int git_path_check_ident(const char *path, struct git_attr_check *check)
{
const char *value = check->value;
return !!ATTR_TRUE(value);
}
static enum crlf_action input_crlf_action(enum crlf_action text_attr, enum eol eol_attr)
{
if (text_attr == CRLF_BINARY)
return CRLF_BINARY;
if (eol_attr == EOL_LF)
return CRLF_INPUT;
if (eol_attr == EOL_CRLF)
return CRLF_CRLF;
return text_attr;
}
struct conv_attrs {
struct convert_driver *drv;
enum crlf_action crlf_action;
enum eol eol_attr;
int ident;
};
static const char *conv_attr_name[] = {
"crlf", "ident", "filter", "eol", "text",
};
#define NUM_CONV_ATTRS ARRAY_SIZE(conv_attr_name)
static void convert_attrs(struct conv_attrs *ca, const char *path)
{
int i;
static struct git_attr_check ccheck[NUM_CONV_ATTRS];
if (!ccheck[0].attr) {
for (i = 0; i < NUM_CONV_ATTRS; i++)
ccheck[i].attr = git_attr(conv_attr_name[i]);
user_convert_tail = &user_convert;
git_config(read_convert_config, NULL);
}
if (!git_check_attr(path, NUM_CONV_ATTRS, ccheck)) {
ca->crlf_action = git_path_check_crlf(path, ccheck + 4);
if (ca->crlf_action == CRLF_GUESS)
ca->crlf_action = git_path_check_crlf(path, ccheck + 0);
ca->ident = git_path_check_ident(path, ccheck + 1);
ca->drv = git_path_check_convert(path, ccheck + 2);
ca->eol_attr = git_path_check_eol(path, ccheck + 3);
} else {
ca->drv = NULL;
ca->crlf_action = CRLF_GUESS;
ca->eol_attr = EOL_UNSET;
ca->ident = 0;
}
}
int convert_to_git(const char *path, const char *src, size_t len,
struct strbuf *dst, enum safe_crlf checksafe)
{
int ret = 0;
const char *filter = NULL;
struct conv_attrs ca;
convert_attrs(&ca, path);
if (ca.drv)
filter = ca.drv->clean;
ret |= apply_filter(path, src, len, dst, filter);
if (ret) {
src = dst->buf;
len = dst->len;
}
ca.crlf_action = input_crlf_action(ca.crlf_action, ca.eol_attr);
ret |= crlf_to_git(path, src, len, dst, ca.crlf_action, checksafe);
if (ret) {
src = dst->buf;
len = dst->len;
}
return ret | ident_to_git(path, src, len, dst, ca.ident);
}
static int convert_to_working_tree_internal(const char *path, const char *src,
size_t len, struct strbuf *dst,
int normalizing)
{
int ret = 0;
const char *filter = NULL;
struct conv_attrs ca;
convert_attrs(&ca, path);
if (ca.drv)
filter = ca.drv->smudge;
ret |= ident_to_worktree(path, src, len, dst, ca.ident);
if (ret) {
src = dst->buf;
len = dst->len;
}
/*
* CRLF conversion can be skipped if normalizing, unless there
* is a smudge filter. The filter might expect CRLFs.
*/
if (filter || !normalizing) {
ca.crlf_action = input_crlf_action(ca.crlf_action, ca.eol_attr);
ret |= crlf_to_worktree(path, src, len, dst, ca.crlf_action);
if (ret) {
src = dst->buf;
len = dst->len;
}
}
return ret | apply_filter(path, src, len, dst, filter);
}
int convert_to_working_tree(const char *path, const char *src, size_t len, struct strbuf *dst)
{
return convert_to_working_tree_internal(path, src, len, dst, 0);
}
int renormalize_buffer(const char *path, const char *src, size_t len, struct strbuf *dst)
{
int ret = convert_to_working_tree_internal(path, src, len, dst, 1);
if (ret) {
src = dst->buf;
len = dst->len;
}
return ret | convert_to_git(path, src, len, dst, 0);
}
/*****************************************************************
*
* Streaming converison support
*
*****************************************************************/
typedef int (*filter_fn)(struct stream_filter *,
const char *input, size_t *isize_p,
char *output, size_t *osize_p);
typedef void (*free_fn)(struct stream_filter *);
struct stream_filter_vtbl {
filter_fn filter;
free_fn free;
};
struct stream_filter {
struct stream_filter_vtbl *vtbl;
};
static int null_filter_fn(struct stream_filter *filter,
const char *input, size_t *isize_p,
char *output, size_t *osize_p)
{
size_t count;
if (!input)
return 0; /* we do not keep any states */
count = *isize_p;
if (*osize_p < count)
count = *osize_p;
if (count) {
memmove(output, input, count);
*isize_p -= count;
*osize_p -= count;
}
return 0;
}
static void null_free_fn(struct stream_filter *filter)
{
; /* nothing -- null instances are shared */
}
static struct stream_filter_vtbl null_vtbl = {
null_filter_fn,
null_free_fn,
};
static struct stream_filter null_filter_singleton = {
&null_vtbl,
};
int is_null_stream_filter(struct stream_filter *filter)
{
return filter == &null_filter_singleton;
}
/*
* LF-to-CRLF filter
*/
struct lf_to_crlf_filter {
struct stream_filter filter;
unsigned want_lf:1;
};
static int lf_to_crlf_filter_fn(struct stream_filter *filter,
const char *input, size_t *isize_p,
char *output, size_t *osize_p)
{
size_t count, o = 0;
struct lf_to_crlf_filter *lf_to_crlf = (struct lf_to_crlf_filter *)filter;
/* Output a pending LF if we need to */
if (lf_to_crlf->want_lf) {
output[o++] = '\n';
lf_to_crlf->want_lf = 0;
}
/* We are told to drain */
if (!input) {
*osize_p -= o;
return 0;
}
count = *isize_p;
if (count) {
size_t i;
for (i = 0; o < *osize_p && i < count; i++) {
char ch = input[i];
if (ch == '\n') {
output[o++] = '\r';
if (o >= *osize_p) {
lf_to_crlf->want_lf = 1;
continue; /* We need to increase i */
}
}
output[o++] = ch;
}
*osize_p -= o;
*isize_p -= i;
}
return 0;
}
static void lf_to_crlf_free_fn(struct stream_filter *filter)
{
free(filter);
}
static struct stream_filter_vtbl lf_to_crlf_vtbl = {
lf_to_crlf_filter_fn,
lf_to_crlf_free_fn,
};
static struct stream_filter *lf_to_crlf_filter(void)
{
struct lf_to_crlf_filter *lf_to_crlf = xcalloc(1, sizeof(*lf_to_crlf));
lf_to_crlf->filter.vtbl = &lf_to_crlf_vtbl;
return (struct stream_filter *)lf_to_crlf;
}
/*
* Cascade filter
*/
#define FILTER_BUFFER 1024
struct cascade_filter {
struct stream_filter filter;
struct stream_filter *one;
struct stream_filter *two;
char buf[FILTER_BUFFER];
int end, ptr;
};
static int cascade_filter_fn(struct stream_filter *filter,
const char *input, size_t *isize_p,
char *output, size_t *osize_p)
{
struct cascade_filter *cas = (struct cascade_filter *) filter;
size_t filled = 0;
size_t sz = *osize_p;
size_t to_feed, remaining;
/*
* input -- (one) --> buf -- (two) --> output
*/
while (filled < sz) {
remaining = sz - filled;
/* do we already have something to feed two with? */
if (cas->ptr < cas->end) {
to_feed = cas->end - cas->ptr;
if (stream_filter(cas->two,
cas->buf + cas->ptr, &to_feed,
output + filled, &remaining))
return -1;
cas->ptr += (cas->end - cas->ptr) - to_feed;
filled = sz - remaining;
continue;
}
/* feed one from upstream and have it emit into our buffer */
to_feed = input ? *isize_p : 0;
if (input && !to_feed)
break;
remaining = sizeof(cas->buf);
if (stream_filter(cas->one,
input, &to_feed,
cas->buf, &remaining))
return -1;
cas->end = sizeof(cas->buf) - remaining;
cas->ptr = 0;
if (input) {
size_t fed = *isize_p - to_feed;
*isize_p -= fed;
input += fed;
}
/* do we know that we drained one completely? */
if (input || cas->end)
continue;
/* tell two to drain; we have nothing more to give it */
to_feed = 0;
remaining = sz - filled;
if (stream_filter(cas->two,
NULL, &to_feed,
output + filled, &remaining))
return -1;
if (remaining == (sz - filled))
break; /* completely drained two */
filled = sz - remaining;
}
*osize_p -= filled;
return 0;
}
static void cascade_free_fn(struct stream_filter *filter)
{
struct cascade_filter *cas = (struct cascade_filter *)filter;
free_stream_filter(cas->one);
free_stream_filter(cas->two);
free(filter);
}
static struct stream_filter_vtbl cascade_vtbl = {
cascade_filter_fn,
cascade_free_fn,
};
static struct stream_filter *cascade_filter(struct stream_filter *one,
struct stream_filter *two)
{
struct cascade_filter *cascade;
if (!one || is_null_stream_filter(one))
return two;
if (!two || is_null_stream_filter(two))
return one;
cascade = xmalloc(sizeof(*cascade));
cascade->one = one;
cascade->two = two;
cascade->end = cascade->ptr = 0;
cascade->filter.vtbl = &cascade_vtbl;
return (struct stream_filter *)cascade;
}
/*
* ident filter
*/
#define IDENT_DRAINING (-1)
#define IDENT_SKIPPING (-2)
struct ident_filter {
struct stream_filter filter;
struct strbuf left;
int state;
char ident[45]; /* ": x40 $" */
};
static int is_foreign_ident(const char *str)
{
int i;
if (prefixcmp(str, "$Id: "))
return 0;
for (i = 5; str[i]; i++) {
if (isspace(str[i]) && str[i+1] != '$')
return 1;
}
return 0;
}
static void ident_drain(struct ident_filter *ident, char **output_p, size_t *osize_p)
{
size_t to_drain = ident->left.len;
if (*osize_p < to_drain)
to_drain = *osize_p;
if (to_drain) {
memcpy(*output_p, ident->left.buf, to_drain);
strbuf_remove(&ident->left, 0, to_drain);
*output_p += to_drain;
*osize_p -= to_drain;
}
if (!ident->left.len)
ident->state = 0;
}
static int ident_filter_fn(struct stream_filter *filter,
const char *input, size_t *isize_p,
char *output, size_t *osize_p)
{
struct ident_filter *ident = (struct ident_filter *)filter;
static const char head[] = "$Id";
if (!input) {
/* drain upon eof */
switch (ident->state) {
default:
strbuf_add(&ident->left, head, ident->state);
case IDENT_SKIPPING:
/* fallthru */
case IDENT_DRAINING:
ident_drain(ident, &output, osize_p);
}
return 0;
}
while (*isize_p || (ident->state == IDENT_DRAINING)) {
int ch;
if (ident->state == IDENT_DRAINING) {
ident_drain(ident, &output, osize_p);
if (!*osize_p)
break;
continue;
}
ch = *(input++);
(*isize_p)--;
if (ident->state == IDENT_SKIPPING) {
/*
* Skipping until '$' or LF, but keeping them
* in case it is a foreign ident.
*/
strbuf_addch(&ident->left, ch);
if (ch != '\n' && ch != '$')
continue;
if (ch == '$' && !is_foreign_ident(ident->left.buf)) {
strbuf_setlen(&ident->left, sizeof(head) - 1);
strbuf_addstr(&ident->left, ident->ident);
}
ident->state = IDENT_DRAINING;
continue;
}
if (ident->state < sizeof(head) &&
head[ident->state] == ch) {
ident->state++;
continue;
}
if (ident->state)
strbuf_add(&ident->left, head, ident->state);
if (ident->state == sizeof(head) - 1) {
if (ch != ':' && ch != '$') {
strbuf_addch(&ident->left, ch);
ident->state = 0;
continue;
}
if (ch == ':') {
strbuf_addch(&ident->left, ch);
ident->state = IDENT_SKIPPING;
} else {
strbuf_addstr(&ident->left, ident->ident);
ident->state = IDENT_DRAINING;
}
continue;
}
strbuf_addch(&ident->left, ch);
ident->state = IDENT_DRAINING;
}
return 0;
}
static void ident_free_fn(struct stream_filter *filter)
{
struct ident_filter *ident = (struct ident_filter *)filter;
strbuf_release(&ident->left);
free(filter);
}
static struct stream_filter_vtbl ident_vtbl = {
ident_filter_fn,
ident_free_fn,
};
static struct stream_filter *ident_filter(const unsigned char *sha1)
{
struct ident_filter *ident = xmalloc(sizeof(*ident));
sprintf(ident->ident, ": %s $", sha1_to_hex(sha1));
strbuf_init(&ident->left, 0);
ident->filter.vtbl = &ident_vtbl;
ident->state = 0;
return (struct stream_filter *)ident;
}
/*
* Return an appropriately constructed filter for the path, or NULL if
* the contents cannot be filtered without reading the whole thing
* in-core.
*
* Note that you would be crazy to set CRLF, smuge/clean or ident to a
* large binary blob you would want us not to slurp into the memory!
*/
struct stream_filter *get_stream_filter(const char *path, const unsigned char *sha1)
{
struct conv_attrs ca;
enum crlf_action crlf_action;
struct stream_filter *filter = NULL;
convert_attrs(&ca, path);
if (ca.drv && (ca.drv->smudge || ca.drv->clean))
return filter;
if (ca.ident)
filter = ident_filter(sha1);
crlf_action = input_crlf_action(ca.crlf_action, ca.eol_attr);
if ((crlf_action == CRLF_BINARY) || (crlf_action == CRLF_INPUT) ||
(crlf_action == CRLF_GUESS && auto_crlf == AUTO_CRLF_FALSE))
filter = cascade_filter(filter, &null_filter_singleton);
else if (output_eol(crlf_action) == EOL_CRLF &&
!(crlf_action == CRLF_AUTO || crlf_action == CRLF_GUESS))
filter = cascade_filter(filter, lf_to_crlf_filter());
return filter;
}
void free_stream_filter(struct stream_filter *filter)
{
filter->vtbl->free(filter);
}
int stream_filter(struct stream_filter *filter,
const char *input, size_t *isize_p,
char *output, size_t *osize_p)
{
return filter->vtbl->filter(filter, input, isize_p, output, osize_p);
}