Update the showlocks utility program so that it functions on files with

a huge number of locks without overflowing the stack.

FossilOrigin-Name: adb7484f93329c7a94cd84e30bc4a8dbf2d6e901eba17cc3454afb8ba346cbf4

diff --git a/manifest b/manifest
index 56768b3a54b7910246e2b911b4f74657815e34a3..f7d92c6d0dc2a46bd59b3be8a26188ba5836dfda 100644 (file)
--- a/manifest
+++ b/manifest
@@ -1,6 +1,6 @@
 B 7a876209a678a34c198b54ceef9e3c041f128a14dc73357f6a57cadadaa6cf7b
-C Add\sthe\sieee754_mantissa()\sand\sieee754_exponent()\sfunctions\sto\sthe\siee754\nextension.\s\sBuild\sthe\sieee754\sextension\sinto\sthe\sCLI.
-D 2020-06-24T15:06:29.041
+C Update\sthe\sshowlocks\sutility\sprogram\sso\sthat\sit\sfunctions\son\sfiles\swith\na\shuge\snumber\sof\slocks\swithout\soverflowing\sthe\sstack.
+D 2020-06-25T23:21:09.249
 F Makefile.in 19374a5db06c3199ec1bab71ab74a103d8abf21053c05e9389255dc58083f806
 F Makefile.msc 48f5a3fc32672c09ad73795749f6253e406a31526935fbbffd8f021108d54574
 F autoconf/Makefile.am a8d1d24affe52ebf8d7ddcf91aa973fa0316618ab95bb68c87cabf8faf527dc8
@@ -16,7 +16,8 @@ F test/speedtest1.c ea201573f9b27542ea1e74a68e74f121e0eb04c89e67039f40ed68f1b833
 F tool/mkautoconfamal.sh f62353eb6c06ab264da027fd4507d09914433dbdcab9cb011cdc18016f1ab3b8
 F tool/mksqlite3c.tcl f4ef476510eca4124c874a72029f1e01bc54a896b1724e8f9eef0d8bfae0e84c
 F tool/mksqlite3h.tcl 1f5e4a1dbbbc43c83cc6e74fe32c6c620502240b66c7c0f33a51378e78fc4edf
-P 838817b680f02b3845d6d56f85d5d36fa5ae7453afef7a1a5a24624255f2dc3e
-R 6e286f8b0cf2dcbbb10b38a65d995df9
+F tool/showlocks.c 9cc5e66d4ebbf2d194f39db2527ece92077e86ae627ddd233ee48e16e8142564
+P db2f0836b64cd2e119684f1cf75fa3b19a84ca6aca1a239f7e2b9298016e2c95
+R 0276be5c8a111d3ffc976288f1457408
 U drh
-Z 549c83ceeab0b10ef9bb12772423a56c
+Z 08b6b193e7afff7dc4e3f0aacc9e50d2

diff --git a/manifest.uuid b/manifest.uuid
index 766ebfb8a35d73c5a87f2c3d0e92c1a243174edb..c071b7db7727c3b4bd9ec7b58847e9f095dbe265 100644 (file)
--- a/manifest.uuid
+++ b/manifest.uuid
@@ -1 +1 @@
-db2f0836b64cd2e119684f1cf75fa3b19a84ca6aca1a239f7e2b9298016e2c95
\ No newline at end of file
+adb7484f93329c7a94cd84e30bc4a8dbf2d6e901eba17cc3454afb8ba346cbf4
\ No newline at end of file

diff --git a/tool/showlocks.c b/tool/showlocks.c
index 752c535cc3719047f85cbea6da0f8741aae42712..4159a71f8ac81fd8b03038bdfa0304057a78796e 100644 (file)
--- a/tool/showlocks.c
+++ b/tool/showlocks.c
@@ -24,23 +24,58 @@
 static int showLocksInRange(int fd, off_t lwr, off_t upr){
   int cnt = 0;
   struct flock x;
+  struct lockRange {
+    off_t lwr;
+    off_t upr;
+  } *aPending = 0;
+  int nAlloc = 1;
+  int nPending = 0;
+  int nDone = 0;
 
-  x.l_type = F_WRLCK;
-  x.l_whence = SEEK_SET;
-  x.l_start = lwr;
-  x.l_len = upr-lwr;
-  fcntl(fd, F_GETLK, &x);
-  if( x.l_type==F_UNLCK ) return 0;
-  printf("start: %-12d len: %-5d pid: %-5d type: %s\n",
-       (int)x.l_start, (int)x.l_len,
-       x.l_pid, x.l_type==F_WRLCK ? "WRLCK" : "RDLCK");
-  cnt++;
-  if( x.l_start>lwr ){
-    cnt += showLocksInRange(fd, lwr, x.l_start-1);
+  nPending = 1;
+  aPending = malloc( sizeof(aPending[0]) );
+  if( aPending==0 ){
+    fprintf(stderr, "out of memory\n");
+    exit(1);
   }
-  if( x.l_start+x.l_len<upr ){
-    cnt += showLocksInRange(fd, x.l_start+x.l_len+1, upr);
+  aPending[0].lwr = lwr;
+  aPending[0].upr = upr;
+
+  for(nDone=0; nDone<nPending; nDone++){
+    lwr = aPending[nDone].lwr;
+    upr = aPending[nDone].upr;
+    if( lwr>=upr ) continue;
+    x.l_type = F_WRLCK;
+    x.l_whence = SEEK_SET;
+    x.l_start = lwr;
+    x.l_len = upr - lwr;
+    fcntl(fd, F_GETLK, &x);
+    if( x.l_type==F_UNLCK ) continue;
+    printf("start: %-12d len: %-5d pid: %-5d type: %s\n",
+         (int)x.l_start, (int)x.l_len,
+         x.l_pid, x.l_type==F_WRLCK ? "WRLCK" : "RDLCK");
+    cnt++;
+    if( nPending+2 > nAlloc ){
+      nAlloc = nAlloc*2 + 2;
+      aPending = realloc(aPending, sizeof(aPending[0])*nAlloc );
+    }
+    if( aPending==0 ){
+      fprintf(stderr, "unable to realloc for %d bytes\n",
+                      (int)sizeof(aPending[0])*(nPending+2));
+      exit(1);
+    }
+    if( lwr<x.l_start ){
+      aPending[nPending].lwr = lwr;
+      aPending[nPending].upr = x.l_start;
+      nPending++;
+    }
+    if( x.l_start+x.l_len<=upr ){
+      aPending[nPending].lwr = x.l_start + x.l_len;
+      aPending[nPending].upr = upr;
+      nPending++;
+    }
   }
+  free(aPending);
   return cnt;
 }