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zorgiepoozorgiepoo
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Change bsdiff's suffix sort algorithm to sais. Fixes sparkle-project#132
Although sparkle-project#132 is marked as closed, the issue is still real. bsdiff can crash or hang when creating diffs on some files. In particular, bsdiff hangs/crashes in its recursive split function. As you can see from: http://stackoverflow.com/a/20305493/871119 https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=409664 bsdiff 4.3 uses qsufsort for its suffix sorting algorithm, which has a bug causing the hanging/crashing. Our solution is to change the algorithm to use sais for suffix sorting: https://sites.google.com/site/yuta256/sais Notes: *I had to change sais_index_type #define from int to off_t in sais.h/c and in some other places, to eliminate all warnings. Compiles cleanly with clang's -Weverything *sais is claimed to be more efficient than other algorithms including qsufsort. If a more efficient (and stable) algorithm comes out, we may be able to swap it out in the future.
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‎LICENSE

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Original file line numberDiff line numberDiff line change
@@ -30,6 +30,9 @@ EXTERNAL LICENSES
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bspatch.c and bsdiff.c, from bsdiff 4.3 <http://www.daemonology.net/bsdiff/>:
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Copyright (c) 2003-2005 Colin Percival.
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sais.c and sais.c, from sais-lite (2010/08/07) <https://sites.google.com/site/yuta256/sais>:
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Copyright (c) 2008-2010 Yuta Mori.
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SUDSAVerifier.m:
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Copyright (c) 2011 Mark Hamlin.
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‎Sparkle.xcodeproj/project.pbxproj

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@@ -167,6 +167,7 @@
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61F83F720DBFE140006FDD30 /* SUBasicUpdateDriver.m in Sources */ = {isa = PBXBuildFile; fileRef = 61F83F700DBFE137006FDD30 /* SUBasicUpdateDriver.m */; };
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61F83F740DBFE141006FDD30 /* SUBasicUpdateDriver.h in Headers */ = {isa = PBXBuildFile; fileRef = 61F83F6F0DBFE137006FDD30 /* SUBasicUpdateDriver.h */; settings = {ATTRIBUTES = (); }; };
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61FA52880E2D9EA400EF58AD /* Sparkle.framework in Frameworks */ = {isa = PBXBuildFile; fileRef = 8DC2EF5B0486A6940098B216 /* Sparkle.framework */; settings = {ATTRIBUTES = (Required, ); }; };
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7223E7631AD1AEFF008E3161 /* sais.c in Sources */ = {isa = PBXBuildFile; fileRef = 7223E7611AD1AEFF008E3161 /* sais.c */; };
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767B61AC1972D488004E0C3C /* SUGuidedPackageInstaller.h in Headers */ = {isa = PBXBuildFile; fileRef = 767B61AA1972D488004E0C3C /* SUGuidedPackageInstaller.h */; };
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767B61AD1972D488004E0C3C /* SUGuidedPackageInstaller.m in Sources */ = {isa = PBXBuildFile; fileRef = 767B61AB1972D488004E0C3C /* SUGuidedPackageInstaller.m */; };
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767B61AE1972D488004E0C3C /* SUGuidedPackageInstaller.m in Sources */ = {isa = PBXBuildFile; fileRef = 767B61AB1972D488004E0C3C /* SUGuidedPackageInstaller.m */; };
@@ -534,6 +535,8 @@
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61F614540E24A12D009F47E7 /* it */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = text.plist.strings; name = it; path = it.lproj/Sparkle.strings; sourceTree = "<group>"; };
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61F83F6F0DBFE137006FDD30 /* SUBasicUpdateDriver.h */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.h; path = SUBasicUpdateDriver.h; sourceTree = "<group>"; };
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61F83F700DBFE137006FDD30 /* SUBasicUpdateDriver.m */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.objc; path = SUBasicUpdateDriver.m; sourceTree = "<group>"; };
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7223E7611AD1AEFF008E3161 /* sais.c */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.c; path = sais.c; sourceTree = "<group>"; };
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7223E7621AD1AEFF008E3161 /* sais.h */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.h; path = sais.h; sourceTree = "<group>"; };
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767B61AA1972D488004E0C3C /* SUGuidedPackageInstaller.h */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.h; path = SUGuidedPackageInstaller.h; sourceTree = "<group>"; };
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767B61AB1972D488004E0C3C /* SUGuidedPackageInstaller.m */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.objc; path = SUGuidedPackageInstaller.m; sourceTree = "<group>"; };
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8DC2EF5A0486A6940098B216 /* Sparkle-Info.plist */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = text.plist.xml; path = "Sparkle-Info.plist"; sourceTree = "<group>"; };
@@ -707,6 +710,8 @@
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5D06E8DB0FD68CB9005AE3F6 /* bsdiff.c */,
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5D06E8DC0FD68CB9005AE3F6 /* bspatch.c */,
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611142E810FB1BE5009810AA /* bspatch.h */,
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7223E7611AD1AEFF008E3161 /* sais.c */,
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7223E7621AD1AEFF008E3161 /* sais.h */,
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);
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path = bsdiff;
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sourceTree = "<group>";
@@ -1395,6 +1400,7 @@
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5D06E8E90FD68CDB005AE3F6 /* bsdiff.c in Sources */,
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14652F7E19A9728A00959E44 /* bspatch.c in Sources */,
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14652F7D19A9726700959E44 /* SUBinaryDeltaApply.m in Sources */,
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7223E7631AD1AEFF008E3161 /* sais.c in Sources */,
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14652F7C19A9725300959E44 /* SUBinaryDeltaCommon.m in Sources */,
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5D06E8EA0FD68CDB005AE3F6 /* SUBinaryDeltaTool.m in Sources */,
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);

‎Vendor/bsdiff/bsdiff.c

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Original file line numberDiff line numberDiff line change
@@ -29,6 +29,7 @@ __FBSDID("$FreeBSD: src/usr.bin/bsdiff/bsdiff/bsdiff.c, v 1.1 2005/08/06 01:59:0
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#endif
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#include <sys/types.h>
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#include "sais.h"
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#include <err.h>
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#include <fcntl.h>
@@ -39,138 +40,6 @@ __FBSDID("$FreeBSD: src/usr.bin/bsdiff/bsdiff/bsdiff.c, v 1.1 2005/08/06 01:59:0
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#define MIN(x, y) (((x)<(y)) ? (x) : (y))
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static void split(off_t *I, off_t *V, off_t start, off_t len, off_t h)
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{
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off_t i, j, k, x, tmp, jj, kk;
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if (len < 16) {
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for (k = start; k < start + len; k += j) {
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j = 1; x = V[I[k] + h];
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for (i = 1; k + i < start + len; i++) {
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if (V[I[k + i] + h] < x) {
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x = V[I[k + i] + h];
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j = 0;
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};
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if (V[I[k + i] + h] == x) {
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tmp = I[k + j]; I[k + j] = I[k + i]; I[k + i] = tmp;
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j++;
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};
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};
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for (i = 0; i < j; i++)
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V[I[k + i]] = k + j - 1;
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if (j == 1)
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I[k] = -1;
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};
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return;
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};
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x = V[I[start + len/2] + h];
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jj = 0; kk = 0;
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for (i = start; i < start + len; i++) {
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if (V[I[i] + h] < x)
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jj++;
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if (V[I[i] + h] == x)
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kk++;
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};
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jj += start; kk += jj;
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i = start; j = 0; k = 0;
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while (i < jj) {
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if (V[I[i] + h] < x) {
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i++;
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} else if (V[I[i] + h] == x) {
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tmp = I[i]; I[i] = I[jj + j]; I[jj + j] = tmp;
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j++;
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} else {
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tmp = I[i]; I[i] = I[kk + k]; I[kk + k] = tmp;
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k++;
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};
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};
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while (jj + j < kk) {
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if (V[I[jj + j] + h] == x) {
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j++;
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} else {
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tmp = I[jj + j]; I[jj + j] = I[kk + k]; I[kk + k] = tmp;
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k++;
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};
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};
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if (jj > start)
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split(I, V, start, jj - start, h);
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for (i = 0; i < kk - jj; i++)
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V[I[jj + i]] = kk - 1;
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if (jj == kk - 1)
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I[jj] = -1;
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if (start + len > kk)
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split(I, V, kk, start + len - kk, h);
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}
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/* qsufsort(I, V, old, oldsize)
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*
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* Computes the suffix sort of the string at 'old' and stores the resulting
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* indices in 'I', using 'V' as a temporary array for the computation. */
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static void qsufsort(off_t *I, off_t *V, u_char *old, off_t oldsize)
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{
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off_t buckets[256];
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off_t i, h, len;
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/* count number of each byte */
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for (i = 0; i < 256; i++)
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buckets[i] = 0;
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for (i = 0; i < oldsize; i++)
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buckets[old[i]]++;
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/* make buckets cumulative */
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for (i = 1; i < 256; i++)
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buckets[i] += buckets[i - 1];
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/* shift right by one */
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for (i = 255; i > 0; i--)
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buckets[i] = buckets[i - 1];
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buckets[0] = 0;
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/* at this point, buckets[c] is the number of bytes in the old file with
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* value less than c. */
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/* set up the sort order of the suffixes based solely on the first
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* character */
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for (i = 0; i < oldsize; i++)
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I[++buckets[old[i]]] = i;
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I[0] = oldsize;
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/* ? */
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for (i = 0; i < oldsize; i++)
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V[i] = buckets[old[i]];
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V[oldsize] = 0;
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/* forward any entries in the ordering which have the same initial
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* character */
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for (i = 1; i < 256; i++) {
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if (buckets[i] == buckets[i - 1] + 1)
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I[buckets[i]] = -1;
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}
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I[0] = -1;
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for (h = 1; I[0] != -(oldsize + 1); h += h) {
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len = 0;
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for (i = 0; i < oldsize + 1;) {
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if (I[i] < 0) {
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len -= I[i];
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i -= I[i];
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} else {
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if (len)
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I[i - len] = -len;
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len = V[I[i]] + 1 - i;
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split(I, V, i, len, h);
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i += len;
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len = 0;
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}
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}
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if (len)
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I[i - len] = -len;
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};
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for (i = 0; i < oldsize + 1; i++) I[V[i]] = i;
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}
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/* matchlen(old, oldsize, new, newsize)
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*
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* Returns the length of the longest common prefix between 'old' and 'new'. */
@@ -288,7 +157,7 @@ int bsdiff(int argc, char *argv[])
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err(1, NULL);
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/* Do a suffix sort on the old file. */
291-
qsufsort(I, V, old, oldsize);
160+
I[0] = oldsize; sais(old, I+1, oldsize);
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free(V);
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