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-rw-r--r--convert.c1297
1 files changed, 1297 insertions, 0 deletions
diff --git a/convert.c b/convert.c
new file mode 100644
index 0000000..2a2e46c
--- /dev/null
+++ b/convert.c
@@ -0,0 +1,1297 @@
+#include "cache.h"
+#include "attr.h"
+#include "run-command.h"
+#include "quote.h"
+#include "sigchain.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)
+{
+ unsigned long sz;
+ void *data;
+ int has_cr;
+
+ data = read_blob_data_from_cache(path, &sz);
+ if (!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) ||
+ (src && !len))
+ return 0;
+
+ /*
+ * If we are doing a dry-run and have no source buffer, there is
+ * nothing to analyze; we must assume we would convert.
+ */
+ if (!buf && !src)
+ return 1;
+
+ 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;
+
+ /*
+ * At this point all of our source analysis is done, and we are sure we
+ * would convert. If we are in dry-run mode, we can give an answer.
+ */
+ if (!buf)
+ return 1;
+
+ /* 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);
+
+ sigchain_push(SIGPIPE, SIG_IGN);
+
+ 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);
+
+ sigchain_pop(SIGPIPE);
+
+ 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;
+
+ if (!dst)
+ return 1;
+
+ 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;
+ int required;
+} *user_convert, **user_convert_tail;
+
+static int read_convert_config(const char *var, const char *value, void *cb)
+{
+ const char *key, *name;
+ int namelen;
+ struct convert_driver *drv;
+
+ /*
+ * External conversion drivers are configured using
+ * "filter.<name>.variable".
+ */
+ if (parse_config_key(var, "filter", &name, &namelen, &key) < 0 || !name)
+ return 0;
+ 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);
+ }
+
+ /*
+ * 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", key))
+ return git_config_string(&drv->smudge, var, value);
+
+ if (!strcmp("clean", key))
+ return git_config_string(&drv->clean, var, value);
+
+ if (!strcmp("required", key)) {
+ drv->required = git_config_bool(var, value);
+ return 0;
+ }
+
+ 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 || (src && !count_ident(src, len)))
+ return 0;
+
+ if (!buf)
+ return 1;
+
+ /* 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 enum crlf_action 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 enum eol 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;
+ int required = 0;
+ struct conv_attrs ca;
+
+ convert_attrs(&ca, path);
+ if (ca.drv) {
+ filter = ca.drv->clean;
+ required = ca.drv->required;
+ }
+
+ ret |= apply_filter(path, src, len, dst, filter);
+ if (!ret && required)
+ die("%s: clean filter '%s' failed", path, ca.drv->name);
+
+ if (ret && dst) {
+ 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 && dst) {
+ 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, ret_filter = 0;
+ const char *filter = NULL;
+ int required = 0;
+ struct conv_attrs ca;
+
+ convert_attrs(&ca, path);
+ if (ca.drv) {
+ filter = ca.drv->smudge;
+ required = ca.drv->required;
+ }
+
+ 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;
+ }
+ }
+
+ ret_filter = apply_filter(path, src, len, dst, filter);
+ if (!ret_filter && required)
+ die("%s: smudge filter %s failed", path, ca.drv->name);
+
+ return ret | ret_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, SAFE_CRLF_FALSE);
+}
+
+/*****************************************************************
+ *
+ * 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 has_held:1;
+ char held;
+};
+
+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;
+
+ /*
+ * We may be holding onto the CR to see if it is followed by a
+ * LF, in which case we would need to go to the main loop.
+ * Otherwise, just emit it to the output stream.
+ */
+ if (lf_to_crlf->has_held && (lf_to_crlf->held != '\r' || !input)) {
+ output[o++] = lf_to_crlf->held;
+ lf_to_crlf->has_held = 0;
+ }
+
+ /* We are told to drain */
+ if (!input) {
+ *osize_p -= o;
+ return 0;
+ }
+
+ count = *isize_p;
+ if (count || lf_to_crlf->has_held) {
+ size_t i;
+ int was_cr = 0;
+
+ if (lf_to_crlf->has_held) {
+ was_cr = 1;
+ lf_to_crlf->has_held = 0;
+ }
+
+ for (i = 0; o < *osize_p && i < count; i++) {
+ char ch = input[i];
+
+ if (ch == '\n') {
+ output[o++] = '\r';
+ } else if (was_cr) {
+ /*
+ * Previous round saw CR and it is not followed
+ * by a LF; emit the CR before processing the
+ * current character.
+ */
+ output[o++] = '\r';
+ }
+
+ /*
+ * We may have consumed the last output slot,
+ * in which case we need to break out of this
+ * loop; hold the current character before
+ * returning.
+ */
+ if (*osize_p <= o) {
+ lf_to_crlf->has_held = 1;
+ lf_to_crlf->held = ch;
+ continue; /* break but increment i */
+ }
+
+ if (ch == '\r') {
+ was_cr = 1;
+ continue;
+ }
+
+ was_cr = 0;
+ output[o++] = ch;
+ }
+
+ *osize_p -= o;
+ *isize_p -= i;
+
+ if (!lf_to_crlf->has_held && was_cr) {
+ lf_to_crlf->has_held = 1;
+ lf_to_crlf->held = '\r';
+ }
+ }
+ 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);
+}