diff options
| -rw-r--r-- | apply.c | 97 |
1 files changed, 82 insertions, 15 deletions
@@ -773,19 +773,20 @@ 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) { - unsigned long start; + int i; + unsigned long start, backwards, forwards; if (fragsize > size) return -1; start = 0; if (line > 1) { - line--; unsigned long offset = 0; - while (start + offset <= size) { + i = line-1; + while (offset + fragsize <= size) { if (buf[offset++] == '\n') { start = offset; - if (!--line) + if (!--i) break; } } @@ -796,13 +797,60 @@ static int find_offset(const char *buf, unsigned long size, const char *fragment return start; /* + * There's probably some smart way to do this, but I'll leave + * that to the smart and beautiful people. I'm simple and stupid. + */ + backwards = start; + forwards = start; + for (i = 0; ; i++) { + unsigned long try; + int n; + + /* "backward" */ + if (i & 1) { + if (!backwards) { + if (forwards + fragsize > size) + break; + continue; + } + do { + --backwards; + } while (backwards && buf[backwards-1] != '\n'); + try = backwards; + } else { + while (forwards + fragsize <= size) { + if (buf[forwards++] == '\n') + break; + } + try = forwards; + } + + if (try + fragsize > size) + continue; + if (memcmp(buf + try, fragment, fragsize)) + continue; + n = (i >> 1)+1; + if (i & 1) + n = -n; + fprintf(stderr, "Fragment applied at offset %d\n", n); + return try; + } + + /* * We should start searching forward and backward. */ return -1; } -static int apply_one_fragment(char *buf, unsigned long *sizep, unsigned long *bufsizep, struct fragment *frag) +struct buffer_desc { + char *buffer; + unsigned long size; + unsigned long alloc; +}; + +static int apply_one_fragment(struct buffer_desc *desc, struct fragment *frag) { + char *buf = desc->buffer; const char *patch = frag->patch; int offset, size = frag->size; char *old = xmalloc(size); @@ -848,9 +896,21 @@ static int apply_one_fragment(char *buf, unsigned long *sizep, unsigned long *bu size -= len; } - offset = find_offset(buf, *sizep, old, oldsize, frag->newpos); + offset = find_offset(buf, desc->size, old, oldsize, frag->newpos); if (offset >= 0) { - printf("found at offset %d\n", offset); + 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; + } + desc->size = size; + memmove(buf + offset + newsize, buf + offset + oldsize, size - offset - newsize); + memcpy(buf + offset, new, newsize); offset = 0; } @@ -859,12 +919,12 @@ static int apply_one_fragment(char *buf, unsigned long *sizep, unsigned long *bu return offset; } -static int apply_fragments(char *buf, unsigned long *sizep, unsigned long *bufsizep, struct patch *patch) +static int apply_fragments(struct buffer_desc *desc, struct patch *patch) { struct fragment *frag = patch->fragments; while (frag) { - if (apply_one_fragment(buf, sizep, bufsizep, frag) < 0) + if (apply_one_fragment(desc, frag) < 0) return error("patch failed: %s:%d", patch->old_name, frag->oldpos); frag = frag->next; } @@ -872,18 +932,25 @@ static int apply_fragments(char *buf, unsigned long *sizep, unsigned long *bufsi static int apply_data(struct patch *patch, struct stat *st) { - unsigned long size, bufsize; - void *buf; + char *buf; + unsigned long size, alloc; + struct buffer_desc desc; if (!patch->old_name || !patch->fragments) return 0; size = st->st_size; - bufsize = size + 16; - buf = xmalloc(bufsize); - if (read_old_data(st, patch->old_name, buf, bufsize) != size) + alloc = size + 8192; + buf = xmalloc(alloc); + if (read_old_data(st, patch->old_name, buf, alloc) != size) return error("read of %s failed", patch->old_name); - if (apply_fragments(buf, &size, &bufsize, patch) < 0) + + desc.size = size; + desc.alloc = alloc; + desc.buffer = buf; + if (apply_fragments(&desc, patch) < 0) return -1; + patch->result = desc.buffer; + patch->resultsize = desc.size; return 0; } |