summaryrefslogtreecommitdiff
path: root/convert.c
diff options
context:
space:
mode:
Diffstat (limited to 'convert.c')
-rw-r--r--convert.c397
1 files changed, 397 insertions, 0 deletions
diff --git a/convert.c b/convert.c
index efc7e07d47..85939c29be 100644
--- a/convert.c
+++ b/convert.c
@@ -813,3 +813,400 @@ int renormalize_buffer(const char *path, const char *src, size_t len, struct str
}
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
+ */
+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;
+
+ if (!input)
+ return 0; /* we do not keep any states */
+ count = *isize_p;
+ if (count) {
+ size_t i, o;
+ for (i = o = 0; o < *osize_p && i < count; i++) {
+ char ch = input[i];
+ if (ch == '\n') {
+ if (o + 1 < *osize_p)
+ output[o++] = '\r';
+ else
+ break;
+ }
+ output[o++] = ch;
+ }
+
+ *osize_p -= o;
+ *isize_p -= i;
+ }
+ return 0;
+}
+
+static struct stream_filter_vtbl lf_to_crlf_vtbl = {
+ lf_to_crlf_filter_fn,
+ null_free_fn,
+};
+
+static struct stream_filter lf_to_crlf_filter_singleton = {
+ &lf_to_crlf_vtbl,
+};
+
+
+/*
+ * 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_singleton);
+
+ 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);
+}