git-remote: exit with non-zero status after detecting errors.
[gitweb.git] / convert.c
index a5f60c7c6b729efbc7b98b1f5ac098cbf1bf9728..21908b10398492c0b07f705ed3b1ce7a06ac6b44 100644 (file)
--- a/convert.c
+++ b/convert.c
@@ -1,5 +1,6 @@
 #include "cache.h"
 #include "attr.h"
+#include "run-command.h"
 
 /*
  * convert.c - convert a file when checking it out and checking it in.
  * translation when the "auto_crlf" option is set.
  */
 
+#define CRLF_GUESS     (-1)
+#define CRLF_BINARY    0
+#define CRLF_TEXT      1
+#define CRLF_INPUT     2
+
 struct text_stat {
        /* CR, LF and CRLF counts */
        unsigned cr, lf, crlf;
@@ -74,192 +80,625 @@ static int is_binary(unsigned long size, struct text_stat *stats)
        return 0;
 }
 
-static int crlf_to_git(const char *path, char **bufp, unsigned long *sizep, int guess)
+static char *crlf_to_git(const char *path, const char *src, unsigned long *sizep, int action)
 {
-       char *buffer, *nbuf;
+       char *buffer, *dst;
        unsigned long size, nsize;
        struct text_stat stats;
 
-       if (guess && !auto_crlf)
-               return 0;
+       if ((action == CRLF_BINARY) || !auto_crlf)
+               return NULL;
 
        size = *sizep;
        if (!size)
-               return 0;
-       buffer = *bufp;
+               return NULL;
 
-       gather_stats(buffer, size, &stats);
+       gather_stats(src, size, &stats);
 
        /* No CR? Nothing to convert, regardless. */
        if (!stats.cr)
-               return 0;
+               return NULL;
 
-       if (guess) {
+       if (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;
+                       return NULL;
 
                /*
                 * And add some heuristics for binary vs text, of course...
                 */
                if (is_binary(size, &stats))
-                       return 0;
+                       return NULL;
        }
 
        /*
-        * Ok, allocate a new buffer, fill it in, and return true
-        * to let the caller know that we switched buffers on it.
+        * Ok, allocate a new buffer, fill it in, and return it
+        * to let the caller know that we switched buffers.
         */
        nsize = size - stats.crlf;
-       nbuf = xmalloc(nsize);
-       *bufp = nbuf;
+       buffer = xmalloc(nsize);
        *sizep = nsize;
 
-       if (guess) {
+       dst = buffer;
+       if (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 = *buffer++;
+                       unsigned char c = *src++;
                        if (c != '\r')
-                               *nbuf++ = c;
+                               *dst++ = c;
                } while (--size);
        } else {
                do {
-                       unsigned char c = *buffer++;
-                       if (! (c == '\r' && (1 < size && *buffer == '\n')))
-                               *nbuf++ = c;
+                       unsigned char c = *src++;
+                       if (! (c == '\r' && (1 < size && *src == '\n')))
+                               *dst++ = c;
                } while (--size);
        }
 
-       return 1;
-}
-
-static int autocrlf_to_git(const char *path, char **bufp, unsigned long *sizep)
-{
-       return crlf_to_git(path, bufp, sizep, 1);
-}
-
-static int forcecrlf_to_git(const char *path, char **bufp, unsigned long *sizep)
-{
-       return crlf_to_git(path, bufp, sizep, 0);
+       return buffer;
 }
 
-static int crlf_to_working_tree(const char *path, char **bufp, unsigned long *sizep, int guess)
+static char *crlf_to_worktree(const char *path, const char *src, unsigned long *sizep, int action)
 {
-       char *buffer, *nbuf;
+       char *buffer, *dst;
        unsigned long size, nsize;
        struct text_stat stats;
        unsigned char last;
 
-       if (guess && auto_crlf <= 0)
-               return 0;
+       if ((action == CRLF_BINARY) || (action == CRLF_INPUT) ||
+           auto_crlf <= 0)
+               return NULL;
 
        size = *sizep;
        if (!size)
-               return 0;
-       buffer = *bufp;
+               return NULL;
 
-       gather_stats(buffer, size, &stats);
+       gather_stats(src, size, &stats);
 
        /* No LF? Nothing to convert, regardless. */
        if (!stats.lf)
-               return 0;
+               return NULL;
 
        /* Was it already in CRLF format? */
        if (stats.lf == stats.crlf)
-               return 0;
+               return NULL;
 
-       if (guess) {
+       if (action == CRLF_GUESS) {
                /* If we have any bare CR characters, we're not going to touch it */
                if (stats.cr != stats.crlf)
-                       return 0;
+                       return NULL;
 
                if (is_binary(size, &stats))
-                       return 0;
+                       return NULL;
        }
 
        /*
-        * Ok, allocate a new buffer, fill it in, and return true
-        * to let the caller know that we switched buffers on it.
+        * Ok, allocate a new buffer, fill it in, and return it
+        * to let the caller know that we switched buffers.
         */
        nsize = size + stats.lf - stats.crlf;
-       nbuf = xmalloc(nsize);
-       *bufp = nbuf;
+       buffer = xmalloc(nsize);
        *sizep = nsize;
        last = 0;
+
+       dst = buffer;
        do {
-               unsigned char c = *buffer++;
+               unsigned char c = *src++;
                if (c == '\n' && last != '\r')
-                       *nbuf++ = '\r';
-               *nbuf++ = c;
+                       *dst++ = '\r';
+               *dst++ = c;
                last = c;
        } while (--size);
 
-       return 1;
+       return buffer;
 }
 
-static int autocrlf_to_working_tree(const char *path, char **bufp, unsigned long *sizep)
+static int filter_buffer(const char *path, const char *src,
+                        unsigned long size, const char *cmd)
 {
-       return crlf_to_working_tree(path, bufp, sizep, 1);
+       /*
+        * Spawn cmd and feed the buffer contents through its stdin.
+        */
+       struct child_process child_process;
+       int pipe_feed[2];
+       int write_err, status;
+
+       memset(&child_process, 0, sizeof(child_process));
+
+       if (pipe(pipe_feed) < 0) {
+               error("cannot create pipe to run external filter %s", cmd);
+               return 1;
+       }
+
+       child_process.pid = fork();
+       if (child_process.pid < 0) {
+               error("cannot fork to run external filter %s", cmd);
+               close(pipe_feed[0]);
+               close(pipe_feed[1]);
+               return 1;
+       }
+       if (!child_process.pid) {
+               dup2(pipe_feed[0], 0);
+               close(pipe_feed[0]);
+               close(pipe_feed[1]);
+               execlp("sh", "sh", "-c", cmd, NULL);
+               return 1;
+       }
+       close(pipe_feed[0]);
+
+       write_err = (write_in_full(pipe_feed[1], src, size) < 0);
+       if (close(pipe_feed[1]))
+               write_err = 1;
+       if (write_err)
+               error("cannot feed the input to external filter %s", cmd);
+
+       status = finish_command(&child_process);
+       if (status)
+               error("external filter %s failed %d", cmd, -status);
+       return (write_err || status);
+}
+
+static char *apply_filter(const char *path, const char *src,
+                         unsigned long *sizep, const char *cmd)
+{
+       /*
+        * Create a pipeline to have the command filter the buffer's
+        * contents.
+        *
+        * (child --> cmd) --> us
+        */
+       const int SLOP = 4096;
+       int pipe_feed[2];
+       int status;
+       char *dst;
+       unsigned long dstsize, dstalloc;
+       struct child_process child_process;
+
+       if (!cmd)
+               return NULL;
+
+       memset(&child_process, 0, sizeof(child_process));
+
+       if (pipe(pipe_feed) < 0) {
+               error("cannot create pipe to run external filter %s", cmd);
+               return NULL;
+       }
+
+       fflush(NULL);
+       child_process.pid = fork();
+       if (child_process.pid < 0) {
+               error("cannot fork to run external filter %s", cmd);
+               close(pipe_feed[0]);
+               close(pipe_feed[1]);
+               return NULL;
+       }
+       if (!child_process.pid) {
+               dup2(pipe_feed[1], 1);
+               close(pipe_feed[0]);
+               close(pipe_feed[1]);
+               exit(filter_buffer(path, src, *sizep, cmd));
+       }
+       close(pipe_feed[1]);
+
+       dstalloc = *sizep;
+       dst = xmalloc(dstalloc);
+       dstsize = 0;
+
+       while (1) {
+               ssize_t numread = xread(pipe_feed[0], dst + dstsize,
+                                       dstalloc - dstsize);
+
+               if (numread <= 0) {
+                       if (!numread)
+                               break;
+                       error("read from external filter %s failed", cmd);
+                       free(dst);
+                       dst = NULL;
+                       break;
+               }
+               dstsize += numread;
+               if (dstalloc <= dstsize + SLOP) {
+                       dstalloc = dstsize + SLOP;
+                       dst = xrealloc(dst, dstalloc);
+               }
+       }
+       if (close(pipe_feed[0])) {
+               error("read from external filter %s failed", cmd);
+               free(dst);
+               dst = NULL;
+       }
+
+       status = finish_command(&child_process);
+       if (status) {
+               error("external filter %s failed %d", cmd, -status);
+               free(dst);
+               dst = NULL;
+       }
+
+       if (dst)
+               *sizep = dstsize;
+       return dst;
 }
 
-static int forcecrlf_to_working_tree(const char *path, char **bufp, unsigned long *sizep)
+static struct convert_driver {
+       const char *name;
+       struct convert_driver *next;
+       char *smudge;
+       char *clean;
+} *user_convert, **user_convert_tail;
+
+static int read_convert_config(const char *var, const char *value)
 {
-       return crlf_to_working_tree(path, bufp, sizep, 0);
+       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) {
+               char *namebuf;
+               drv = xcalloc(1, sizeof(struct convert_driver));
+               namebuf = xmalloc(namelen + 1);
+               memcpy(namebuf, name, namelen);
+               namebuf[namelen] = 0;
+               drv->name = namebuf;
+               drv->next = NULL;
+               *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)) {
+               if (!value)
+                       return error("%s: lacks value", var);
+               drv->smudge = strdup(value);
+               return 0;
+       }
+
+       if (!strcmp("clean", ep)) {
+               if (!value)
+                       return error("%s: lacks value", var);
+               drv->clean = strdup(value);
+               return 0;
+       }
+       return 0;
 }
 
-static void setup_crlf_check(struct git_attr_check *check)
+static void setup_convert_check(struct git_attr_check *check)
 {
        static struct git_attr *attr_crlf;
+       static struct git_attr *attr_ident;
+       static struct git_attr *attr_filter;
 
-       if (!attr_crlf)
+       if (!attr_crlf) {
                attr_crlf = git_attr("crlf", 4);
-       check->attr = attr_crlf;
+               attr_ident = git_attr("ident", 5);
+               attr_filter = git_attr("filter", 6);
+               user_convert_tail = &user_convert;
+               git_config(read_convert_config);
+       }
+       check[0].attr = attr_crlf;
+       check[1].attr = attr_ident;
+       check[2].attr = attr_filter;
+}
+
+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;
+                       }
+               }
+       }
+       return cnt;
 }
 
-static int git_path_check_crlf(const char *path)
+static char *ident_to_git(const char *path, const char *src, unsigned long *sizep, int ident)
 {
-       struct git_attr_check attr_crlf_check;
-
-       setup_crlf_check(&attr_crlf_check);
-
-       if (!git_checkattr(path, 1, &attr_crlf_check)) {
-               const char *value = attr_crlf_check.value;
-               if (ATTR_TRUE(value))
-                       return 1;
-               else if (ATTR_FALSE(value))
-                       return 0;
-               else if (ATTR_UNSET(value))
-                       ;
+       int cnt;
+       unsigned long size;
+       char *dst, *buf;
+
+       if (!ident)
+               return NULL;
+       size = *sizep;
+       cnt = count_ident(src, size);
+       if (!cnt)
+               return NULL;
+       buf = xmalloc(size);
+
+       for (dst = buf; size; size--) {
+               char ch = *src++;
+               *dst++ = ch;
+               if ((ch == '$') && (3 <= size) &&
+                   !memcmp("Id:", src, 3)) {
+                       unsigned long rem = size - 3;
+                       const char *cp = src + 3;
+                       do {
+                               ch = *cp++;
+                               if (ch == '$')
+                                       break;
+                               rem--;
+                       } while (rem);
+                       if (!rem)
+                               continue;
+                       memcpy(dst, "Id$", 3);
+                       dst += 3;
+                       size -= (cp - src);
+                       src = cp;
+               }
+       }
+
+       *sizep = dst - buf;
+       return buf;
+}
+
+static char *ident_to_worktree(const char *path, const char *src, unsigned long *sizep, int ident)
+{
+       int cnt;
+       unsigned long size;
+       char *dst, *buf;
+       unsigned char sha1[20];
+
+       if (!ident)
+               return NULL;
+
+       size = *sizep;
+       cnt = count_ident(src, size);
+       if (!cnt)
+               return NULL;
+
+       hash_sha1_file(src, size, "blob", sha1);
+       buf = xmalloc(size + cnt * 43);
+
+       for (dst = buf; size; size--) {
+               const char *cp;
+               /* Fetch next source character, move the pointer on */
+               char ch = *src++;
+               /* Copy the current character to the destination */
+               *dst++ = ch;
+               /* If the current character is "$" or there are less than three
+                * remaining bytes or the two bytes following this one are not
+                * "Id", then simply read the next character */
+               if ((ch != '$') || (size < 3) || memcmp("Id", src, 2))
+                       continue;
+               /*
+                * Here when
+                *  - There are more than 2 bytes remaining
+                *  - The current three bytes are "$Id"
+                * with
+                *  - ch == "$"
+                *  - src[0] == "I"
+                */
+
+               /*
+                * It's possible that an expanded Id has crept its way into the
+                * repository, we cope with that by stripping the expansion out
+                */
+               if (src[2] == ':') {
+                       /* Expanded keywords have "$Id:" at the front */
+
+                       /* discard up to but not including the closing $ */
+                       unsigned long rem = size - 3;
+                       /* Point at first byte after the ":" */
+                       cp = src + 3;
+                       /*
+                        * Throw away characters until either
+                        *  - we reach a "$"
+                        *  - we run out of bytes (rem == 0)
+                        */
+                       do {
+                               ch = *cp;
+                               if (ch == '$')
+                                       break;
+                               cp++;
+                               rem--;
+                       } while (rem);
+                       /* If the above finished because it ran out of characters, then
+                        * this is an incomplete keyword, so don't run the expansion */
+                       if (!rem)
+                               continue;
+               } else if (src[2] == '$')
+                       cp = src + 2;
                else
-                       die("unknown value %s given to 'crlf' attribute",
-                           (char *)value);
+                       /* Anything other than "$Id:XXX$" or $Id$ and we skip the
+                        * expansion */
+                       continue;
+
+               /* cp is now pointing at the last $ of the keyword */
+
+               memcpy(dst, "Id: ", 4);
+               dst += 4;
+               memcpy(dst, sha1_to_hex(sha1), 40);
+               dst += 40;
+               *dst++ = ' ';
+
+               /* Adjust for the characters we've discarded */
+               size -= (cp - src);
+               src = cp;
+
+               /* Copy the final "$" */
+               *dst++ = *src++;
+               size--;
        }
-       return -1;
+
+       *sizep = dst - buf;
+       return buf;
 }
 
-int convert_to_git(const char *path, char **bufp, unsigned long *sizep)
+static int git_path_check_crlf(const char *path, struct git_attr_check *check)
 {
-       switch (git_path_check_crlf(path)) {
-       case 0:
-               return 0;
-       case 1:
-               return forcecrlf_to_git(path, bufp, sizep);
-       default:
-               return autocrlf_to_git(path, bufp, sizep);
+       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;
+       return CRLF_GUESS;
+}
+
+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);
+}
+
+char *convert_to_git(const char *path, const char *src, unsigned long *sizep)
+{
+       struct git_attr_check check[3];
+       int crlf = CRLF_GUESS;
+       int ident = 0;
+       char *filter = NULL;
+       char *buf, *buf2;
+
+       setup_convert_check(check);
+       if (!git_checkattr(path, ARRAY_SIZE(check), check)) {
+               struct convert_driver *drv;
+               crlf = git_path_check_crlf(path, check + 0);
+               ident = git_path_check_ident(path, check + 1);
+               drv = git_path_check_convert(path, check + 2);
+               if (drv && drv->clean)
+                       filter = drv->clean;
        }
+
+       buf = apply_filter(path, src, sizep, filter);
+
+       buf2 = crlf_to_git(path, buf ? buf : src, sizep, crlf);
+       if (buf2) {
+               free(buf);
+               buf = buf2;
+       }
+
+       buf2 = ident_to_git(path, buf ? buf : src, sizep, ident);
+       if (buf2) {
+               free(buf);
+               buf = buf2;
+       }
+
+       return buf;
 }
 
-int convert_to_working_tree(const char *path, char **bufp, unsigned long *sizep)
+char *convert_to_working_tree(const char *path, const char *src, unsigned long *sizep)
 {
-       switch (git_path_check_crlf(path)) {
-       case 0:
-               return 0;
-       case 1:
-               return forcecrlf_to_working_tree(path, bufp, sizep);
-       default:
-               return autocrlf_to_working_tree(path, bufp, sizep);
+       struct git_attr_check check[3];
+       int crlf = CRLF_GUESS;
+       int ident = 0;
+       char *filter = NULL;
+       char *buf, *buf2;
+
+       setup_convert_check(check);
+       if (!git_checkattr(path, ARRAY_SIZE(check), check)) {
+               struct convert_driver *drv;
+               crlf = git_path_check_crlf(path, check + 0);
+               ident = git_path_check_ident(path, check + 1);
+               drv = git_path_check_convert(path, check + 2);
+               if (drv && drv->smudge)
+                       filter = drv->smudge;
+       }
+
+       buf = ident_to_worktree(path, src, sizep, ident);
+
+       buf2 = crlf_to_worktree(path, buf ? buf : src, sizep, crlf);
+       if (buf2) {
+               free(buf);
+               buf = buf2;
+       }
+
+       buf2 = apply_filter(path, buf ? buf : src, sizep, filter);
+       if (buf2) {
+               free(buf);
+               buf = buf2;
+       }
+
+       return buf;
+}
+
+void *convert_sha1_file(const char *path, const unsigned char *sha1,
+                        unsigned int mode, enum object_type *type,
+                        unsigned long *size)
+{
+       void *buffer = read_sha1_file(sha1, type, size);
+       if (S_ISREG(mode) && buffer) {
+               void *converted = convert_to_working_tree(path, buffer, size);
+               if (converted) {
+                       free(buffer);
+                       buffer = converted;
+               }
        }
+       return buffer;
 }