expose a helper function peel_to_type().
[gitweb.git] / convert.c
index c64880bdf589028af7ac67cd12e8aa55b41b1fc7..d8c94cb3edeceff7a79b2f5e6ba7cad250e6b301 100644 (file)
--- a/convert.c
+++ b/convert.c
@@ -17,8 +17,8 @@
 #define CRLF_INPUT     2
 
 struct text_stat {
-       /* CR, LF and CRLF counts */
-       unsigned cr, lf, crlf;
+       /* NUL, CR, LF and CRLF counts */
+       unsigned nul, cr, lf, crlf;
 
        /* These are just approximations! */
        unsigned printable, nonprintable;
@@ -51,6 +51,9 @@ static void gather_stats(const char *buf, unsigned long size, struct text_stat *
                        case '\b': case '\t': case '\033': case '\014':
                                stats->printable++;
                                break;
+                       case 0:
+                               stats->nul++;
+                               /* fall through */
                        default:
                                stats->nonprintable++;
                        }
@@ -66,6 +69,8 @@ static void gather_stats(const char *buf, unsigned long size, struct text_stat *
 static int is_binary(unsigned long size, struct text_stat *stats)
 {
 
+       if (stats->nul)
+               return 1;
        if ((stats->printable >> 7) < stats->nonprintable)
                return 1;
        /*
@@ -80,24 +85,47 @@ static int is_binary(unsigned long size, struct text_stat *stats)
        return 0;
 }
 
-static char *crlf_to_git(const char *path, const char *src, unsigned long *sizep, int action)
+static void check_safe_crlf(const char *path, int action,
+                            struct text_stat *stats, enum safe_crlf checksafe)
 {
-       char *buffer, *dst;
-       unsigned long size, nsize;
-       struct text_stat stats;
+       if (!checksafe)
+               return;
 
-       if ((action == CRLF_BINARY) || (action == CRLF_GUESS && !auto_crlf))
-               return NULL;
+       if (action == CRLF_INPUT || auto_crlf <= 0) {
+               /*
+                * 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.", path);
+                       else /* i.e. SAFE_CRLF_FAIL */
+                               die("CRLF would be replaced by LF in %s.", path);
+               }
+       } else if (auto_crlf > 0) {
+               /*
+                * 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", path);
+                       else /* i.e. SAFE_CRLF_FAIL */
+                               die("LF would be replaced by CRLF in %s", path);
+               }
+       }
+}
 
-       size = *sizep;
-       if (!size)
-               return NULL;
+static int crlf_to_git(const char *path, const char *src, size_t len,
+                       struct strbuf *buf, int action, enum safe_crlf checksafe)
+{
+       struct text_stat stats;
+       char *dst;
 
-       gather_stats(src, size, &stats);
+       if ((action == CRLF_BINARY) || !auto_crlf || !len)
+               return 0;
 
-       /* No CR? Nothing to convert, regardless. */
-       if (!stats.cr)
-               return NULL;
+       gather_stats(src, len, &stats);
 
        if (action == CRLF_GUESS) {
                /*
@@ -106,24 +134,25 @@ static char *crlf_to_git(const char *path, const char *src, unsigned long *sizep
                 * stuff?
                 */
                if (stats.cr != stats.crlf)
-                       return NULL;
+                       return 0;
 
                /*
                 * And add some heuristics for binary vs text, of course...
                 */
-               if (is_binary(size, &stats))
-                       return NULL;
+               if (is_binary(len, &stats))
+                       return 0;
        }
 
-       /*
-        * Ok, allocate a new buffer, fill it in, and return it
-        * to let the caller know that we switched buffers.
-        */
-       nsize = size - stats.crlf;
-       buffer = xmalloc(nsize);
-       *sizep = nsize;
+       check_safe_crlf(path, action, &stats, checksafe);
 
-       dst = buffer;
+       /* 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 (action == CRLF_GUESS) {
                /*
                 * If we guessed, we already know we rejected a file with
@@ -134,120 +163,112 @@ static char *crlf_to_git(const char *path, const char *src, unsigned long *sizep
                        unsigned char c = *src++;
                        if (c != '\r')
                                *dst++ = c;
-               } while (--size);
+               } while (--len);
        } else {
                do {
                        unsigned char c = *src++;
-                       if (! (c == '\r' && (1 < size && *src == '\n')))
+                       if (! (c == '\r' && (1 < len && *src == '\n')))
                                *dst++ = c;
-               } while (--size);
+               } while (--len);
        }
-
-       return buffer;
+       strbuf_setlen(buf, dst - buf->buf);
+       return 1;
 }
 
-static char *crlf_to_worktree(const char *path, const char *src, unsigned long *sizep, int action)
+static int crlf_to_worktree(const char *path, const char *src, size_t len,
+                            struct strbuf *buf, int action)
 {
-       char *buffer, *dst;
-       unsigned long size, nsize;
+       char *to_free = NULL;
        struct text_stat stats;
-       unsigned char last;
 
        if ((action == CRLF_BINARY) || (action == CRLF_INPUT) ||
-           (action == CRLF_GUESS && auto_crlf <= 0))
-               return NULL;
+           auto_crlf <= 0)
+               return 0;
 
-       size = *sizep;
-       if (!size)
-               return NULL;
+       if (!len)
+               return 0;
 
-       gather_stats(src, size, &stats);
+       gather_stats(src, len, &stats);
 
        /* No LF? Nothing to convert, regardless. */
        if (!stats.lf)
-               return NULL;
+               return 0;
 
        /* Was it already in CRLF format? */
        if (stats.lf == stats.crlf)
-               return NULL;
+               return 0;
 
        if (action == CRLF_GUESS) {
                /* If we have any bare CR characters, we're not going to touch it */
                if (stats.cr != stats.crlf)
-                       return NULL;
+                       return 0;
 
-               if (is_binary(size, &stats))
-                       return NULL;
+               if (is_binary(len, &stats))
+                       return 0;
        }
 
-       /*
-        * 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;
-       buffer = xmalloc(nsize);
-       *sizep = nsize;
-       last = 0;
-
-       dst = buffer;
-       do {
-               unsigned char c = *src++;
-               if (c == '\n' && last != '\r')
-                       *dst++ = '\r';
-               *dst++ = c;
-               last = c;
-       } while (--size);
-
-       return buffer;
+       /* 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;
 }
 
-static int filter_buffer(const char *path, const char *src,
-                        unsigned long size, const char *cmd)
+struct filter_params {
+       const char *src;
+       unsigned long size;
+       const char *cmd;
+};
+
+static int filter_buffer(int fd, void *data)
 {
        /*
         * Spawn cmd and feed the buffer contents through its stdin.
         */
        struct child_process child_process;
-       int pipe_feed[2];
+       struct filter_params *params = (struct filter_params *)data;
        int write_err, status;
+       const char *argv[] = { "sh", "-c", params->cmd, NULL };
 
        memset(&child_process, 0, sizeof(child_process));
+       child_process.argv = argv;
+       child_process.in = -1;
+       child_process.out = fd;
 
-       if (pipe(pipe_feed) < 0) {
-               error("cannot create pipe to run external filter %s", cmd);
-               return 1;
-       }
+       if (start_command(&child_process))
+               return error("cannot fork to run external filter %s", params->cmd);
 
-       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 = (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", cmd);
+               error("cannot feed the input to external filter %s", params->cmd);
 
        status = finish_command(&child_process);
        if (status)
-               error("external filter %s failed %d", cmd, -status);
+               error("external filter %s failed %d", params->cmd, -status);
        return (write_err || status);
 }
 
-static char *apply_filter(const char *path, const char *src,
-                         unsigned long *sizep, const char *cmd)
+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
@@ -255,77 +276,44 @@ static char *apply_filter(const char *path, const char *src,
         *
         * (child --> cmd) --> us
         */
-       const int SLOP = 4096;
-       int pipe_feed[2];
-       int status;
-       char *dst;
-       unsigned long dstsize, dstalloc;
-       struct child_process child_process;
+       int ret = 1;
+       struct strbuf nbuf;
+       struct async async;
+       struct filter_params params;
 
        if (!cmd)
-               return NULL;
-
-       memset(&child_process, 0, sizeof(child_process));
+               return 0;
 
-       if (pipe(pipe_feed) < 0) {
-               error("cannot create pipe to run external filter %s", cmd);
-               return NULL;
-       }
+       memset(&async, 0, sizeof(async));
+       async.proc = filter_buffer;
+       async.data = &params;
+       params.src = src;
+       params.size = len;
+       params.cmd = cmd;
 
        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;
+       if (start_async(&async))
+               return 0;       /* error was already reported */
 
-       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);
-               }
+       strbuf_init(&nbuf, 0);
+       if (strbuf_read(&nbuf, async.out, len) < 0) {
+               error("read from external filter %s failed", cmd);
+               ret = 0;
        }
-       if (close(pipe_feed[0])) {
+       if (close(async.out)) {
                error("read from external filter %s failed", cmd);
-               free(dst);
-               dst = NULL;
+               ret = 0;
        }
-
-       status = finish_command(&child_process);
-       if (status) {
-               error("external filter %s failed %d", cmd, -status);
-               free(dst);
-               dst = NULL;
+       if (finish_async(&async)) {
+               error("external filter %s failed", cmd);
+               ret = 0;
        }
 
-       if (dst)
-               *sizep = dstsize;
-       return dst;
+       if (ret) {
+               strbuf_swap(dst, &nbuf);
+       }
+       strbuf_release(&nbuf);
+       return ret;
 }
 
 static struct convert_driver {
@@ -353,13 +341,8 @@ static int read_convert_config(const char *var, const char *value)
                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;
+               drv->name = xmemdupz(name, namelen);
                *user_convert_tail = drv;
                user_convert_tail = &(drv->next);
        }
@@ -377,14 +360,14 @@ static int read_convert_config(const char *var, const char *value)
 
        if (!strcmp("smudge", ep)) {
                if (!value)
-                       return error("%s: lacks value", var);
+                       return config_error_nonbool(var);
                drv->smudge = strdup(value);
                return 0;
        }
 
        if (!strcmp("clean", ep)) {
                if (!value)
-                       return error("%s: lacks value", var);
+                       return config_error_nonbool(var);
                drv->clean = strdup(value);
                return 0;
        }
@@ -449,102 +432,106 @@ static int count_ident(const char *cp, unsigned long size)
        return cnt;
 }
 
-static char *ident_to_git(const char *path, const char *src, unsigned long *sizep, int ident)
+static int ident_to_git(const char *path, const char *src, size_t len,
+                        struct strbuf *buf, int ident)
 {
-       int cnt;
-       unsigned long size;
-       char *dst, *buf;
+       char *dst, *dollar;
 
-       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;
+       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, '$', len);
+               if (!dollar)
+                       break;
+               memcpy(dst, src, dollar + 1 - src);
+               dst += dollar + 1 - src;
+               len -= dollar + 1 - src;
+               src  = dollar + 1;
+
+               if (len > 3 && !memcmp(src, "Id:", 3)) {
+                       dollar = memchr(src + 3, '$', len - 3);
+                       if (!dollar)
+                               break;
                        memcpy(dst, "Id$", 3);
                        dst += 3;
-                       size -= (cp - src);
-                       src = cp;
+                       len -= dollar + 1 - src;
+                       src  = dollar + 1;
                }
        }
-
-       *sizep = dst - buf;
-       return buf;
+       memcpy(dst, src, len);
+       strbuf_setlen(buf, dst + len - buf->buf);
+       return 1;
 }
 
-static char *ident_to_worktree(const char *path, const char *src, unsigned long *sizep, int ident)
+static int ident_to_worktree(const char *path, const char *src, size_t len,
+                             struct strbuf *buf, int ident)
 {
-       int cnt;
-       unsigned long size;
-       char *dst, *buf;
        unsigned char sha1[20];
+       char *to_free = NULL, *dollar;
+       int cnt;
 
        if (!ident)
-               return NULL;
+               return 0;
 
-       size = *sizep;
-       cnt = count_ident(src, size);
+       cnt = count_ident(src, len);
        if (!cnt)
-               return NULL;
+               return 0;
 
-       hash_sha1_file(src, size, "blob", sha1);
-       buf = xmalloc(size + cnt * 43);
+       /* are we "faking" in place editing ? */
+       if (src == buf->buf)
+               to_free = strbuf_detach(buf, NULL);
+       hash_sha1_file(src, len, "blob", sha1);
 
-       for (dst = buf; size; size--) {
-               const char *cp;
-               char ch = *src++;
-               *dst++ = ch;
-               if ((ch != '$') || (size < 3) || memcmp("Id", src, 2))
+       strbuf_grow(buf, len + cnt * 43);
+       for (;;) {
+               /* step 1: run to the next '$' */
+               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;
 
-               if (src[2] == ':') {
-                       /* discard up to but not including the closing $ */
-                       unsigned long rem = size - 3;
-                       cp = src + 3;
-                       do {
-                               ch = *cp++;
-                               if (ch == '$')
-                                       break;
-                               rem--;
-                       } while (rem);
-                       if (!rem)
-                               continue;
-                       size -= (cp - src);
-               } else if (src[2] == '$')
-                       cp = src + 2;
-               else
+               /* step 3: skip over Id$ or Id:xxxxx$ */
+               if (src[2] == '$') {
+                       src += 3;
+                       len -= 3;
+               } else if (src[2] == ':') {
+                       /*
+                        * It's possible that an expanded Id has crept its way into the
+                        * repository, we cope with that by stripping the expansion out
+                        */
+                       dollar = memchr(src + 3, '$', len - 3);
+                       if (!dollar) {
+                               /* incomplete keyword, no more '$', so just quit the loop */
+                               break;
+                       }
+
+                       len -= dollar + 1 - src;
+                       src  = dollar + 1;
+               } else {
+                       /* it wasn't a "Id$" or "Id:xxxx$" */
                        continue;
+               }
 
-               memcpy(dst, "Id: ", 4);
-               dst += 4;
-               memcpy(dst, sha1_to_hex(sha1), 40);
-               dst += 40;
-               *dst++ = ' ';
-               size -= (cp - src);
-               src = cp;
-               *dst++ = *src++;
-               size--;
+               /* step 4: substitute */
+               strbuf_addstr(buf, "Id: ");
+               strbuf_add(buf, sha1_to_hex(sha1), 40);
+               strbuf_addstr(buf, " $");
        }
+       strbuf_add(buf, src, len);
 
-       *sizep = dst - buf;
-       return buf;
+       free(to_free);
+       return 1;
 }
 
 static int git_path_check_crlf(const char *path, struct git_attr_check *check)
@@ -583,13 +570,13 @@ static int git_path_check_ident(const char *path, struct git_attr_check *check)
        return !!ATTR_TRUE(value);
 }
 
-char *convert_to_git(const char *path, const char *src, unsigned long *sizep)
+int convert_to_git(const char *path, const char *src, size_t len,
+                   struct strbuf *dst, enum safe_crlf checksafe)
 {
        struct git_attr_check check[3];
        int crlf = CRLF_GUESS;
-       int ident = 0;
+       int ident = 0, ret = 0;
        char *filter = NULL;
-       char *buf, *buf2;
 
        setup_convert_check(check);
        if (!git_checkattr(path, ARRAY_SIZE(check), check)) {
@@ -601,30 +588,25 @@ char *convert_to_git(const char *path, const char *src, unsigned long *sizep)
                        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;
+       ret |= apply_filter(path, src, len, dst, filter);
+       if (ret) {
+               src = dst->buf;
+               len = dst->len;
        }
-
-       buf2 = ident_to_git(path, buf ? buf : src, sizep, ident);
-       if (buf2) {
-               free(buf);
-               buf = buf2;
+       ret |= crlf_to_git(path, src, len, dst, crlf, checksafe);
+       if (ret) {
+               src = dst->buf;
+               len = dst->len;
        }
-
-       return buf;
+       return ret | ident_to_git(path, src, len, dst, ident);
 }
 
-char *convert_to_working_tree(const char *path, const char *src, unsigned long *sizep)
+int convert_to_working_tree(const char *path, const char *src, size_t len, struct strbuf *dst)
 {
        struct git_attr_check check[3];
        int crlf = CRLF_GUESS;
-       int ident = 0;
+       int ident = 0, ret = 0;
        char *filter = NULL;
-       char *buf, *buf2;
 
        setup_convert_check(check);
        if (!git_checkattr(path, ARRAY_SIZE(check), check)) {
@@ -636,34 +618,15 @@ char *convert_to_working_tree(const char *path, const char *src, unsigned long *
                        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;
+       ret |= ident_to_worktree(path, src, len, dst, ident);
+       if (ret) {
+               src = dst->buf;
+               len = dst->len;
        }
-
-       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;
-               }
+       ret |= crlf_to_worktree(path, src, len, dst, crlf);
+       if (ret) {
+               src = dst->buf;
+               len = dst->len;
        }
-       return buffer;
+       return ret | apply_filter(path, src, len, dst, filter);
 }