Protocol switch from using generators to stream-like objects.
This allows the the pull side to precisely control how much data is
read so that another encapsulation layer is not needed.
An http client gets a response with a finite size. Because ssh clients
need to keep the stream open, we must not read more data than is sent
in a response. But due to the streaming nature of the changegroup
scheme, only the piece that's parsing the data knows how far it's
allowed to read.
This means the generator scheme isn't fine-grained enough. Instead we
need file-like objects with a read(x) method. This switches everything
for push/pull over to using file-like objects rather than generators.
# mdiff.py - diff and patch routines for mercurial
#
# Copyright 2005 Matt Mackall <mpm@selenic.com>
#
# This software may be used and distributed according to the terms
# of the GNU General Public License, incorporated herein by reference.
import difflib, struct, bdiff
from mpatch import *
def unidiff(a, ad, b, bd, fn, r=None):
if not a and not b: return ""
if a == None:
b = b.splitlines(1)
l1 = "--- %s\t%s\n" % ("/dev/null", ad)
l2 = "+++ %s\t%s\n" % ("b/" + fn, bd)
l3 = "@@ -0,0 +1,%d @@\n" % len(b)
l = [l1, l2, l3] + ["+" + e for e in b]
elif b == None:
a = a.splitlines(1)
l1 = "--- %s\t%s\n" % ("a/" + fn, ad)
l2 = "+++ %s\t%s\n" % ("/dev/null", bd)
l3 = "@@ -1,%d +0,0 @@\n" % len(a)
l = [l1, l2, l3] + ["-" + e for e in a]
else:
a = a.splitlines(1)
b = b.splitlines(1)
l = list(difflib.unified_diff(a, b, "a/" + fn, "b/" + fn))
if not l: return ""
# difflib uses a space, rather than a tab
l[0] = l[0][:-2] + "\t" + ad + "\n"
l[1] = l[1][:-2] + "\t" + bd + "\n"
for ln in xrange(len(l)):
if l[ln][-1] != '\n':
l[ln] += "\n\ No newline at end of file\n"
if r:
l.insert(0, "diff %s %s\n" %
(' '.join(["-r %s" % rev for rev in r]), fn))
return "".join(l)
def sortdiff(a, b):
la = lb = 0
lena = len(a)
lenb = len(b)
while 1:
am, bm, = la, lb
# walk over matching lines
while lb < lenb and la < lena and a[la] == b[lb] :
la += 1
lb += 1
if la > am:
yield (am, bm, la - am) # return a match
# skip mismatched lines from b
while la < lena and lb < lenb and b[lb] < a[la]:
lb += 1
if lb >= lenb:
break
# skip mismatched lines from a
while la < lena and lb < lenb and b[lb] > a[la]:
la += 1
if la >= lena:
break
yield (lena, lenb, 0)
def diff(a, b, sorted=0):
if not a:
s = "".join(b)
return s and (struct.pack(">lll", 0, 0, len(s)) + s)
bin = []
p = [0]
for i in a: p.append(p[-1] + len(i))
if sorted:
try:
d = sortdiff(a, b)
except:
raise
else:
d = difflib.SequenceMatcher(None, a, b).get_matching_blocks()
la = 0
lb = 0
for am, bm, size in d:
s = "".join(b[lb:bm])
if am > la or s:
bin.append(struct.pack(">lll", p[la], p[am], len(s)) + s)
la = am + size
lb = bm + size
return "".join(bin)
def patchtext(bin):
pos = 0
t = []
while pos < len(bin):
p1, p2, l = struct.unpack(">lll", bin[pos:pos + 12])
pos += 12
t.append(bin[pos:pos + l])
pos += l
return "".join(t)
def patch(a, bin):
return patches(a, [bin])
textdiff = bdiff.bdiff