change bounds check to greater-equals to avoid arithmetic in loops
Project: http://git-wip-us.apache.org/repos/asf/commons-compress/repo Commit: http://git-wip-us.apache.org/repos/asf/commons-compress/commit/0c75ccec Tree: http://git-wip-us.apache.org/repos/asf/commons-compress/tree/0c75ccec Diff: http://git-wip-us.apache.org/repos/asf/commons-compress/diff/0c75ccec Branch: refs/heads/master Commit: 0c75ccec267ce902ff36278ba928b4573f4fb937 Parents: ccf4ce7 Author: Stefan Bodewig <bode...@apache.org> Authored: Sat Dec 30 10:53:34 2017 +0100 Committer: Stefan Bodewig <bode...@apache.org> Committed: Sat Dec 30 10:53:34 2017 +0100 ---------------------------------------------------------------------- .../bzip2/BZip2CompressorInputStream.java | 63 ++++++++++---------- 1 file changed, 32 insertions(+), 31 deletions(-) ---------------------------------------------------------------------- http://git-wip-us.apache.org/repos/asf/commons-compress/blob/0c75ccec/src/main/java/org/apache/commons/compress/compressors/bzip2/BZip2CompressorInputStream.java ---------------------------------------------------------------------- diff --git a/src/main/java/org/apache/commons/compress/compressors/bzip2/BZip2CompressorInputStream.java b/src/main/java/org/apache/commons/compress/compressors/bzip2/BZip2CompressorInputStream.java index 06e2bee..945ba3c 100644 --- a/src/main/java/org/apache/commons/compress/compressors/bzip2/BZip2CompressorInputStream.java +++ b/src/main/java/org/apache/commons/compress/compressors/bzip2/BZip2CompressorInputStream.java @@ -399,12 +399,12 @@ public class BZip2CompressorInputStream extends CompressorInputStream implements return bsR(bin, 32); } - private static void checkBounds(final int checkVal, final int limitInclusive, String name) + private static void checkBounds(final int checkVal, final int limitExclusive, String name) throws IOException { if (checkVal < 0) { throw new IOException("Corrupted input, " + name + " value negative"); } - if (checkVal > limitInclusive) { + if (checkVal >= limitExclusive) { throw new IOException("Corrupted input, " + name + " value too big"); } } @@ -431,7 +431,7 @@ public class BZip2CompressorInputStream extends CompressorInputStream implements for (int i = 0; i < alphaSize; i++) { final int l = length[i]; - checkBounds(l, MAX_ALPHA_SIZE - 1, "length"); + checkBounds(l, MAX_ALPHA_SIZE, "length"); base[l + 1]++; } @@ -487,9 +487,9 @@ public class BZip2CompressorInputStream extends CompressorInputStream implements /* Now the selectors */ final int nGroups = bsR(bin, 3); final int nSelectors = bsR(bin, 15); - checkBounds(alphaSize, MAX_ALPHA_SIZE, "alphaSize"); - checkBounds(nGroups, N_GROUPS, "nGroups"); - checkBounds(nSelectors, MAX_SELECTORS, "nSelectors"); + checkBounds(alphaSize, MAX_ALPHA_SIZE + 1, "alphaSize"); + checkBounds(nGroups, N_GROUPS + 1, "nGroups"); + checkBounds(nSelectors, MAX_SELECTORS + 1, "nSelectors"); for (int i = 0; i < nSelectors; i++) { int j = 0; @@ -506,7 +506,7 @@ public class BZip2CompressorInputStream extends CompressorInputStream implements for (int i = 0; i < nSelectors; i++) { int v = selectorMtf[i] & 0xff; - checkBounds(v, N_GROUPS - 1, "selectorMtf"); + checkBounds(v, N_GROUPS, "selectorMtf"); final byte tmp = pos[v]; while (v > 0) { // nearly all times v is zero, 4 in most other cases @@ -599,7 +599,7 @@ public class BZip2CompressorInputStream extends CompressorInputStream implements int nextSym = getAndMoveToFrontDecode0(); int lastShadow = -1; int zt = selector[groupNo] & 0xff; - checkBounds(zt, N_GROUPS - 1, "zt"); + checkBounds(zt, N_GROUPS, "zt"); int[] base_zt = base[zt]; int[] limit_zt = limit[zt]; int[] perm_zt = perm[zt]; @@ -620,9 +620,9 @@ public class BZip2CompressorInputStream extends CompressorInputStream implements if (groupPos == 0) { groupPos = G_SIZE - 1; - checkBounds(++groupNo, MAX_SELECTORS - 1, "groupNo"); + checkBounds(++groupNo, MAX_SELECTORS, "groupNo"); zt = selector[groupNo] & 0xff; - checkBounds(zt, N_GROUPS - 1, "zt"); + checkBounds(zt, N_GROUPS, "zt"); base_zt = base[zt]; limit_zt = limit[zt]; perm_zt = perm[zt]; @@ -632,19 +632,19 @@ public class BZip2CompressorInputStream extends CompressorInputStream implements } int zn = minLens_zt; - checkBounds(zn, MAX_ALPHA_SIZE - 1, "zn"); + checkBounds(zn, MAX_ALPHA_SIZE, "zn"); int zvec = bsR(bin, zn); while(zvec > limit_zt[zn]) { - checkBounds(++zn, MAX_ALPHA_SIZE - 1, "zn"); + checkBounds(++zn, MAX_ALPHA_SIZE, "zn"); zvec = (zvec << 1) | bsR(bin, 1); } final int tmp = zvec - base_zt[zn]; - checkBounds(tmp, MAX_ALPHA_SIZE - 1, "zvec"); + checkBounds(tmp, MAX_ALPHA_SIZE, "zvec"); nextSym = perm_zt[tmp]; } final int yy_0 = yy[0]; - checkBounds(yy_0, 255, "yy"); + checkBounds(yy_0, 256, "yy"); final byte ch = seqToUnseq[yy_0]; unzftab[ch & 0xff] += s + 1; @@ -659,10 +659,10 @@ public class BZip2CompressorInputStream extends CompressorInputStream implements if (++lastShadow >= limitLast) { throw new IOException("block overrun"); } - checkBounds(nextSym, 256, "nextSym"); + checkBounds(nextSym, 256 + 1, "nextSym"); final char tmp = yy[nextSym - 1]; - checkBounds(tmp, 255, "yy"); + checkBounds(tmp, 256, "yy"); unzftab[seqToUnseq[tmp] & 0xff]++; ll8[lastShadow] = seqToUnseq[tmp]; @@ -683,9 +683,9 @@ public class BZip2CompressorInputStream extends CompressorInputStream implements if (groupPos == 0) { groupPos = G_SIZE - 1; - checkBounds(++groupNo, MAX_SELECTORS - 1, "groupNo"); + checkBounds(++groupNo, MAX_SELECTORS, "groupNo"); zt = selector[groupNo] & 0xff; - checkBounds(zt, N_GROUPS - 1, "zt"); + checkBounds(zt, N_GROUPS, "zt"); base_zt = base[zt]; limit_zt = limit[zt]; perm_zt = perm[zt]; @@ -695,14 +695,14 @@ public class BZip2CompressorInputStream extends CompressorInputStream implements } int zn = minLens_zt; - checkBounds(zn, MAX_ALPHA_SIZE - 1, "zn"); + checkBounds(zn, MAX_ALPHA_SIZE, "zn"); int zvec = bsR(bin, zn); while(zvec > limit_zt[zn]) { - checkBounds(++zn, MAX_ALPHA_SIZE - 1, "zn"); + checkBounds(++zn, MAX_ALPHA_SIZE, "zn"); zvec = (zvec << 1) | bsR(bin, 1); } final int idx = zvec - base_zt[zn]; - checkBounds(idx, MAX_ALPHA_SIZE - 1, "zvec"); + checkBounds(idx, MAX_ALPHA_SIZE, "zvec"); nextSym = perm_zt[idx]; } } @@ -713,17 +713,17 @@ public class BZip2CompressorInputStream extends CompressorInputStream implements private int getAndMoveToFrontDecode0() throws IOException { final Data dataShadow = this.data; final int zt = dataShadow.selector[0] & 0xff; - checkBounds(zt, N_GROUPS - 1, "zt"); + checkBounds(zt, N_GROUPS, "zt"); final int[] limit_zt = dataShadow.limit[zt]; int zn = dataShadow.minLens[zt]; - checkBounds(zn, MAX_ALPHA_SIZE - 1, "zn"); + checkBounds(zn, MAX_ALPHA_SIZE, "zn"); int zvec = bsR(bin, zn); while (zvec > limit_zt[zn]) { - checkBounds(++zn, MAX_ALPHA_SIZE - 1, "zn"); + checkBounds(++zn, MAX_ALPHA_SIZE, "zn"); zvec = (zvec << 1) | bsR(bin, 1); } final int tmp = zvec - dataShadow.base[zt][zn]; - checkBounds(tmp, MAX_ALPHA_SIZE - 1, "zvec"); + checkBounds(tmp, MAX_ALPHA_SIZE, "zvec"); return dataShadow.perm[zt][tmp]; } @@ -734,7 +734,8 @@ public class BZip2CompressorInputStream extends CompressorInputStream implements } final int[] cftab = this.data.cftab; - final int[] tt = this.data.initTT(this.last + 1); + final int ttLen = this.last + 1; + final int[] tt = this.data.initTT(ttLen); final byte[] ll8 = this.data.ll8; cftab[0] = 0; System.arraycopy(this.data.unzftab, 0, cftab, 1, 256); @@ -746,7 +747,7 @@ public class BZip2CompressorInputStream extends CompressorInputStream implements for (int i = 0, lastShadow = this.last; i <= lastShadow; i++) { final int tmp = cftab[ll8[i] & 0xff]++; - checkBounds(tmp, this.last, "tt index"); + checkBounds(tmp, ttLen, "tt index"); tt[tmp] = i; } @@ -771,7 +772,7 @@ public class BZip2CompressorInputStream extends CompressorInputStream implements if (this.su_i2 <= this.last) { this.su_chPrev = this.su_ch2; int su_ch2Shadow = this.data.ll8[this.su_tPos] & 0xff; - checkBounds(this.su_tPos, this.data.tt.length - 1, "su_tPos"); + checkBounds(this.su_tPos, this.data.tt.length, "su_tPos"); this.su_tPos = this.data.tt[this.su_tPos]; if (this.su_rNToGo == 0) { this.su_rNToGo = Rand.rNums(this.su_rTPos) - 1; @@ -797,7 +798,7 @@ public class BZip2CompressorInputStream extends CompressorInputStream implements this.su_chPrev = this.su_ch2; final int su_ch2Shadow = this.data.ll8[this.su_tPos] & 0xff; this.su_ch2 = su_ch2Shadow; - checkBounds(this.su_tPos, this.data.tt.length - 1, "su_tPos"); + checkBounds(this.su_tPos, this.data.tt.length, "su_tPos"); this.su_tPos = this.data.tt[this.su_tPos]; this.su_i2++; this.currentState = NO_RAND_PART_B_STATE; @@ -817,7 +818,7 @@ public class BZip2CompressorInputStream extends CompressorInputStream implements return setupRandPartA(); } else if (++this.su_count >= 4) { this.su_z = (char) (this.data.ll8[this.su_tPos] & 0xff); - checkBounds(this.su_tPos, this.data.tt.length - 1, "su_tPos"); + checkBounds(this.su_tPos, this.data.tt.length, "su_tPos"); this.su_tPos = this.data.tt[this.su_tPos]; if (this.su_rNToGo == 0) { this.su_rNToGo = Rand.rNums(this.su_rTPos) - 1; @@ -856,7 +857,7 @@ public class BZip2CompressorInputStream extends CompressorInputStream implements this.su_count = 1; return setupNoRandPartA(); } else if (++this.su_count >= 4) { - checkBounds(this.su_tPos, this.data.ll8.length - 1, "su_tPos"); + checkBounds(this.su_tPos, this.data.ll8.length, "su_tPos"); this.su_z = (char) (this.data.ll8[this.su_tPos] & 0xff); this.su_tPos = this.data.tt[this.su_tPos]; this.su_j2 = 0;
