Mercurial > hg
view mercurial/pure/mpatch.py @ 31758:04ec317b8128
hgweb: expose a followlines UI in filerevision view
In filerevision view (/file/<rev>/<fname>) we add some event listeners on
mouse clicks of <span> elements in the <pre class="sourcelines"> block.
Those listeners will capture a range of lines selected between two mouse
clicks and a box inviting to follow the history of selected lines will then
show up. Selected lines (i.e. the block of lines) get a CSS class which make
them highlighted. Selection can be cancelled (and restarted) by either
clicking on the cancel ("x") button in the invite box or clicking on any other
source line. Also clicking twice on the same line will abort the selection and
reset event listeners to restart the process.
As a first step, this action is only advertised by the "cursor: cell" CSS rule
on source lines elements as any other mechanisms would make the code
significantly more complicated. This might be improved later.
All JavaScript code lives in a new "linerangelog.js" file, sourced in
filerevision template (only in "paper" style for now).
author | Denis Laxalde <denis.laxalde@logilab.fr> |
---|---|
date | Wed, 29 Mar 2017 22:26:16 +0200 |
parents | f2846d546645 |
children | 151cc3b3d799 |
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# mpatch.py - Python implementation of mpatch.c # # Copyright 2009 Matt Mackall <mpm@selenic.com> and others # # This software may be used and distributed according to the terms of the # GNU General Public License version 2 or any later version. from __future__ import absolute_import import struct from . import policy, pycompat stringio = pycompat.stringio modulepolicy = policy.policy policynocffi = policy.policynocffi class mpatchError(Exception): """error raised when a delta cannot be decoded """ # This attempts to apply a series of patches in time proportional to # the total size of the patches, rather than patches * len(text). This # means rather than shuffling strings around, we shuffle around # pointers to fragments with fragment lists. # # When the fragment lists get too long, we collapse them. To do this # efficiently, we do all our operations inside a buffer created by # mmap and simply use memmove. This avoids creating a bunch of large # temporary string buffers. def _pull(dst, src, l): # pull l bytes from src while l: f = src.pop() if f[0] > l: # do we need to split? src.append((f[0] - l, f[1] + l)) dst.append((l, f[1])) return dst.append(f) l -= f[0] def _move(m, dest, src, count): """move count bytes from src to dest The file pointer is left at the end of dest. """ m.seek(src) buf = m.read(count) m.seek(dest) m.write(buf) def _collect(m, buf, list): start = buf for l, p in reversed(list): _move(m, buf, p, l) buf += l return (buf - start, start) def patches(a, bins): if not bins: return a plens = [len(x) for x in bins] pl = sum(plens) bl = len(a) + pl tl = bl + bl + pl # enough for the patches and two working texts b1, b2 = 0, bl if not tl: return a m = stringio() # load our original text m.write(a) frags = [(len(a), b1)] # copy all the patches into our segment so we can memmove from them pos = b2 + bl m.seek(pos) for p in bins: m.write(p) for plen in plens: # if our list gets too long, execute it if len(frags) > 128: b2, b1 = b1, b2 frags = [_collect(m, b1, frags)] new = [] end = pos + plen last = 0 while pos < end: m.seek(pos) try: p1, p2, l = struct.unpack(">lll", m.read(12)) except struct.error: raise mpatchError("patch cannot be decoded") _pull(new, frags, p1 - last) # what didn't change _pull([], frags, p2 - p1) # what got deleted new.append((l, pos + 12)) # what got added pos += l + 12 last = p2 frags.extend(reversed(new)) # what was left at the end t = _collect(m, b2, frags) m.seek(t[1]) return m.read(t[0]) def patchedsize(orig, delta): outlen, last, bin = 0, 0, 0 binend = len(delta) data = 12 while data <= binend: decode = delta[bin:bin + 12] start, end, length = struct.unpack(">lll", decode) if start > end: break bin = data + length data = bin + 12 outlen += start - last last = end outlen += length if bin != binend: raise mpatchError("patch cannot be decoded") outlen += orig - last return outlen if modulepolicy not in policynocffi: try: from _mpatch_cffi import ffi, lib except ImportError: if modulepolicy == 'cffi': # strict cffi import raise else: @ffi.def_extern() def cffi_get_next_item(arg, pos): all, bins = ffi.from_handle(arg) container = ffi.new("struct mpatch_flist*[1]") to_pass = ffi.new("char[]", str(bins[pos])) all.append(to_pass) r = lib.mpatch_decode(to_pass, len(to_pass) - 1, container) if r < 0: return ffi.NULL return container[0] def patches(text, bins): lgt = len(bins) all = [] if not lgt: return text arg = (all, bins) patch = lib.mpatch_fold(ffi.new_handle(arg), lib.cffi_get_next_item, 0, lgt) if not patch: raise mpatchError("cannot decode chunk") outlen = lib.mpatch_calcsize(len(text), patch) if outlen < 0: lib.mpatch_lfree(patch) raise mpatchError("inconsistency detected") buf = ffi.new("char[]", outlen) if lib.mpatch_apply(buf, text, len(text), patch) < 0: lib.mpatch_lfree(patch) raise mpatchError("error applying patches") res = ffi.buffer(buf, outlen)[:] lib.mpatch_lfree(patch) return res