From 0fe7b968ddeec3bbfda5fe17fa5fef11ba7d1dcf Mon Sep 17 00:00:00 2001
From: drh <>
Date: Wed, 29 Oct 2025 13:59:25 +0000
Subject: [PATCH] Send an sqlite3_log() message if the unix backend takes a
 short read.

FossilOrigin-Name: 62fcdbcd67eb0f63c0d19e576a52cfb2b28f4b2efc63c8fd182d6eda5aaebeef
---
 manifest      | 17 ++++++++++-------
 manifest.tags |  4 ++--
 manifest.uuid |  2 +-
 src/os_unix.c |  5 +++++
 4 files changed, 18 insertions(+), 10 deletions(-)

diff --git a/manifest b/manifest
index 438e07a0f7..56c2c9a5ff 100644
--- a/manifest
+++ b/manifest
@@ -1,5 +1,5 @@
-C Tiny\scosmetic\stweak\sto\sconfigure\sscript\soutput.\sNo\sfunctional\schanges.
-D 2025-10-28T22:09:43.464
+C Send\san\ssqlite3_log()\smessage\sif\sthe\sunix\sbackend\stakes\sa\sshort\sread.
+D 2025-10-29T13:59:25.559
 F .fossil-settings/binary-glob 61195414528fb3ea9693577e1980230d78a1f8b0a54c78cf1b9b24d0a409ed6a x
 F .fossil-settings/empty-dirs dbb81e8fc0401ac46a1491ab34a7f2c7c0452f2f06b54ebb845d024ca8283ef1
 F .fossil-settings/ignore-glob 35175cdfcf539b2318cb04a9901442804be81cd677d8b889fcc9149c21f239ea
@@ -720,7 +720,7 @@ F src/os.h 1ff5ae51d339d0e30d8a9d814f4b8f8e448169304d83a7ed9db66a65732f3e63
 F src/os_common.h 6c0eb8dd40ef3e12fe585a13e709710267a258e2c8dd1c40b1948a1d14582e06
 F src/os_kv.c fb7ba8d6204197357f1eb7e1c7450d09c10043bf7e99aba602f4aa46b8fb11a3
 F src/os_setup.h 8efc64eda6a6c2f221387eefc2e7e45fd5a3d5c8337a7a83519ba4fbd2957ae2
-F src/os_unix.c d4fd1c9bd8948c07071fbf5e4ef827f249b9075f31d3706ecc6481ed4e0ba46d
+F src/os_unix.c c73953493af0acf181fb8dd663ec3177b6341cfeba8e8d4e32501dd695dd3ba3
 F src/os_win.c 27617f334168644b542c9d58ac6e5f051b318136273e78d243384b4eca2df6b3
 F src/os_win.h 4c247cdb6d407c75186c94a1e84d5a22cbae4adcec93fcae8d2bc1f956fd1f19
 F src/pager.c 113f9149092ccff6cf90e97c2611200e5a237f13d26c394bc9fd933377852764
@@ -2171,8 +2171,11 @@ F tool/version-info.c 33d0390ef484b3b1cb685d59362be891ea162123cea181cb8e6d2cf6dd
 F tool/warnings-clang.sh bbf6a1e685e534c92ec2bfba5b1745f34fb6f0bc2a362850723a9ee87c1b31a7
 F tool/warnings.sh 1ad0169b022b280bcaaf94a7fa231591be96b514230ab5c98fbf15cd7df842dd
 F tool/win/sqlite.vsix deb315d026cc8400325c5863eef847784a219a2f
-P 26ddec291696dd99c7f84a21b2dd272ce9bf32598ca38413ac89432d45527f8d
-R 84e32fda291a8d058dbadfbda7579a4c
-U stephan
-Z bf4855b54f4310a4966a592dc20188b6
+P e2c20aa5929e5b79aabca8a51fb3e32e0533526d64d7576d3caf1c847fff58b4
+R 44b0bd229c6046b42de11cf0769658d6
+T *branch * log-short-read
+T *sym-log-short-read *
+T -sym-trunk *
+U drh
+Z 50781366ea4ba85a13324005301770a1
 # Remove this line to create a well-formed Fossil manifest.
diff --git a/manifest.tags b/manifest.tags
index bec971799f..e3a93e7f4a 100644
--- a/manifest.tags
+++ b/manifest.tags
@@ -1,2 +1,2 @@
-branch trunk
-tag trunk
+branch log-short-read
+tag log-short-read
diff --git a/manifest.uuid b/manifest.uuid
index a04200fb96..8a40a1a19d 100644
--- a/manifest.uuid
+++ b/manifest.uuid
@@ -1 +1 @@
-e2c20aa5929e5b79aabca8a51fb3e32e0533526d64d7576d3caf1c847fff58b4
+62fcdbcd67eb0f63c0d19e576a52cfb2b28f4b2efc63c8fd182d6eda5aaebeef
diff --git a/src/os_unix.c b/src/os_unix.c
index 7a4cfcb15c..78e24f0416 100644
--- a/src/os_unix.c
+++ b/src/os_unix.c
@@ -3561,6 +3561,11 @@ static int unixRead(
     }
     return SQLITE_IOERR_READ;
   }else{
+    if( amt>=512 ){
+      sqlite3_log(SQLITE_IOERR_SHORT_READ,
+        "Got only %d of %d bytes requested from offset %lld of file \"%s\"",
+        got, amt, offset, pFile->zPath);
+    }
     storeLastErrno(pFile, 0);   /* not a system error */
     /* Unread parts of the buffer must be zero-filled */
     memset(&((char*)pBuf)[got], 0, amt-got);
-- 
2.47.3