builtin-grep: -L (--files-without-match).
[gitweb.git] / apply.c
diff --git a/apply.c b/apply.c
index cc3f12e5557d1b6c333c890d6d0209aee74742e5..269210a578262b22fbf50bbdd9bf9fbccec3202b 100644 (file)
--- a/apply.c
+++ b/apply.c
@@ -32,8 +32,9 @@ static int apply = 1;
 static int no_add = 0;
 static int show_index_info = 0;
 static int line_termination = '\n';
+static unsigned long p_context = -1;
 static const char apply_usage[] =
-"git-apply [--stat] [--numstat] [--summary] [--check] [--index] [--apply] [--no-add] [--index-info] [--allow-binary-replacement] [-z] [-pNUM] [--whitespace=<nowarn|warn|error|error-all|strip>] <patch>...";
+"git-apply [--stat] [--numstat] [--summary] [--check] [--index] [--apply] [--no-add] [--index-info] [--allow-binary-replacement] [-z] [-pNUM] [-CNUM] [--whitespace=<nowarn|warn|error|error-all|strip>] <patch>...";
 
 static enum whitespace_eol {
        nowarn_whitespace,
@@ -100,6 +101,7 @@ static int max_change, max_len;
 static int linenr = 1;
 
 struct fragment {
+       unsigned long leading, trailing;
        unsigned long oldpos, oldlines;
        unsigned long newpos, newlines;
        const char *patch;
@@ -817,12 +819,15 @@ static int parse_fragment(char *line, unsigned long size, struct patch *patch, s
        int added, deleted;
        int len = linelen(line, size), offset;
        unsigned long oldlines, newlines;
+       unsigned long leading, trailing;
 
        offset = parse_fragment_header(line, len, fragment);
        if (offset < 0)
                return -1;
        oldlines = fragment->oldlines;
        newlines = fragment->newlines;
+       leading = 0;
+       trailing = 0;
 
        if (patch->is_new < 0) {
                patch->is_new =  !oldlines;
@@ -860,10 +865,14 @@ static int parse_fragment(char *line, unsigned long size, struct patch *patch, s
                case ' ':
                        oldlines--;
                        newlines--;
+                       if (!deleted && !added)
+                               leading++;
+                       trailing++;
                        break;
                case '-':
                        deleted++;
                        oldlines--;
+                       trailing = 0;
                        break;
                case '+':
                        /*
@@ -887,6 +896,7 @@ static int parse_fragment(char *line, unsigned long size, struct patch *patch, s
                        }
                        added++;
                        newlines--;
+                       trailing = 0;
                        break;
 
                 /* We allow "\ No newline at end of file". Depending
@@ -904,6 +914,9 @@ static int parse_fragment(char *line, unsigned long size, struct patch *patch, s
        }
        if (oldlines || newlines)
                return -1;
+       fragment->leading = leading;
+       fragment->trailing = trailing;
+
        /* If a fragment ends with an incomplete line, we failed to include
         * it in the above loop because we hit oldlines == newlines == 0
         * before seeing it.
@@ -925,8 +938,7 @@ static int parse_single_patch(char *line, unsigned long size, struct patch *patc
                struct fragment *fragment;
                int len;
 
-               fragment = xmalloc(sizeof(*fragment));
-               memset(fragment, 0, sizeof(*fragment));
+               fragment = xcalloc(1, sizeof(*fragment));
                len = parse_fragment(line, size, patch, fragment);
                if (len <= 0)
                        die("corrupt patch at line %d", linenr);
@@ -1088,7 +1100,7 @@ static int read_old_data(struct stat *st, const char *path, void *buf, unsigned
        }
 }
 
-static int find_offset(const char *buf, unsigned long size, const char *fragment, unsigned long fragsize, int line)
+static int find_offset(const char *buf, unsigned long size, const char *fragment, unsigned long fragsize, int line, int *lines)
 {
        int i;
        unsigned long start, backwards, forwards;
@@ -1149,6 +1161,7 @@ static int find_offset(const char *buf, unsigned long size, const char *fragment
                n = (i >> 1)+1;
                if (i & 1)
                        n = -n;
+               *lines = n;
                return try;
        }
 
@@ -1158,6 +1171,33 @@ static int find_offset(const char *buf, unsigned long size, const char *fragment
        return -1;
 }
 
+static void remove_first_line(const char **rbuf, int *rsize)
+{
+       const char *buf = *rbuf;
+       int size = *rsize;
+       unsigned long offset;
+       offset = 0;
+       while (offset <= size) {
+               if (buf[offset++] == '\n')
+                       break;
+       }
+       *rsize = size - offset;
+       *rbuf = buf + offset;
+}
+
+static void remove_last_line(const char **rbuf, int *rsize)
+{
+       const char *buf = *rbuf;
+       int size = *rsize;
+       unsigned long offset;
+       offset = size - 1;
+       while (offset > 0) {
+               if (buf[--offset] == '\n')
+                       break;
+       }
+       *rsize = offset + 1;
+}
+
 struct buffer_desc {
        char *buffer;
        unsigned long size;
@@ -1193,7 +1233,10 @@ static int apply_one_fragment(struct buffer_desc *desc, struct fragment *frag)
        int offset, size = frag->size;
        char *old = xmalloc(size);
        char *new = xmalloc(size);
+       const char *oldlines, *newlines;
        int oldsize = 0, newsize = 0;
+       unsigned long leading, trailing;
+       int pos, lines;
 
        while (size > 0) {
                int len = linelen(patch, size);
@@ -1242,23 +1285,59 @@ static int apply_one_fragment(struct buffer_desc *desc, struct fragment *frag)
                newsize--;
        }
 #endif
-                       
-       offset = find_offset(buf, desc->size, old, oldsize, frag->newpos);
-       if (offset >= 0) {
-               int diff = newsize - oldsize;
-               unsigned long size = desc->size + diff;
-               unsigned long alloc = desc->alloc;
-
-               if (size > alloc) {
-                       alloc = size + 8192;
-                       desc->alloc = alloc;
-                       buf = xrealloc(buf, alloc);
-                       desc->buffer = buf;
+
+       oldlines = old;
+       newlines = new;
+       leading = frag->leading;
+       trailing = frag->trailing;
+       lines = 0;
+       pos = frag->newpos;
+       for (;;) {
+               offset = find_offset(buf, desc->size, oldlines, oldsize, pos, &lines);
+               if (offset >= 0) {
+                       int diff = newsize - oldsize;
+                       unsigned long size = desc->size + diff;
+                       unsigned long alloc = desc->alloc;
+
+                       /* Warn if it was necessary to reduce the number
+                        * of context lines.
+                        */
+                       if ((leading != frag->leading) || (trailing != frag->trailing))
+                               fprintf(stderr, "Context reduced to (%ld/%ld) to apply fragment at %d\n",
+                                       leading, trailing, pos + lines);
+
+                       if (size > alloc) {
+                               alloc = size + 8192;
+                               desc->alloc = alloc;
+                               buf = xrealloc(buf, alloc);
+                               desc->buffer = buf;
+                       }
+                       desc->size = size;
+                       memmove(buf + offset + newsize, buf + offset + oldsize, size - offset - newsize);
+                       memcpy(buf + offset, newlines, newsize);
+                       offset = 0;
+
+                       break;
+               }
+
+               /* Am I at my context limits? */
+               if ((leading <= p_context) && (trailing <= p_context))
+                       break;
+               /* Reduce the number of context lines
+                * Reduce both leading and trailing if they are equal
+                * otherwise just reduce the larger context.
+                */
+               if (leading >= trailing) {
+                       remove_first_line(&oldlines, &oldsize);
+                       remove_first_line(&newlines, &newsize);
+                       pos--;
+                       leading--;
+               }
+               if (trailing > leading) {
+                       remove_last_line(&oldlines, &oldsize);
+                       remove_last_line(&newlines, &newsize);
+                       trailing--;
                }
-               desc->size = size;
-               memmove(buf + offset + newsize, buf + offset + oldsize, size - offset - newsize);
-               memcpy(buf + offset, new, newsize);
-               offset = 0;
        }
 
        free(old);
@@ -1652,8 +1731,7 @@ static void add_index_file(const char *path, unsigned mode, void *buf, unsigned
        if (!write_index)
                return;
 
-       ce = xmalloc(ce_size);
-       memset(ce, 0, ce_size);
+       ce = xcalloc(1, ce_size);
        memcpy(ce->name, path, namelen);
        ce->ce_mode = create_ce_mode(mode);
        ce->ce_flags = htons(namelen);
@@ -1809,8 +1887,7 @@ static int apply_patch(int fd, const char *filename)
                struct patch *patch;
                int nr;
 
-               patch = xmalloc(sizeof(*patch));
-               memset(patch, 0, sizeof(*patch));
+               patch = xcalloc(1, sizeof(*patch));
                nr = parse_chunk(buffer + offset, size, patch);
                if (nr < 0)
                        break;
@@ -1885,6 +1962,7 @@ int main(int argc, char **argv)
 
        for (i = 1; i < argc; i++) {
                const char *arg = argv[i];
+               char *end;
                int fd;
 
                if (!strcmp(arg, "-")) {
@@ -1948,6 +2026,12 @@ int main(int argc, char **argv)
                        line_termination = 0;
                        continue;
                }
+               if (!strncmp(arg, "-C", 2)) {
+                       p_context = strtoul(arg + 2, &end, 0);
+                       if (*end != '\0')
+                               die("unrecognized context count '%s'", arg + 2);
+                       continue;
+               }
                if (!strncmp(arg, "--whitespace=", 13)) {
                        whitespace_option = arg + 13;
                        parse_whitespace_option(arg + 13);