[Lldb-commits] [lldb] [lldb] Remove limit on max memory read size (PR #105765)

[Jason Molenda via lldb-commits]

https://github.com/jasonmolenda created https://github.com/llvm/llvm-project/pull/105765

`memory read` will return an error if you try to read more than 1k bytes in a single command, instructing you to set
`target.max-memory-read-size` or use `--force` if you intended to read more than that.  This is a safeguard for a command where people are being explicit about how much memory they would like lldb to read (either to display, or save to a file) and is an annoyance every time you need to read more than a small amount.  If someone confuses the --count argument with the start address, lldb may begin dumping gigabytes of data but I'd rather that behavior than requiring everyone to special-case their way around a common use case.

I don't want to remove the setting because many people have added (much larger) default max read sizes to their ~/.lldbinit files after hitting this behavior.  Another option would be to stop reading/using the value in Target.cpp, but I see no harm in leaving the setting if someone really does prefer to have a small cap on their memory read size.

>From 6a27ad3be748a6072014a805a5a94dede9321432 Mon Sep 17 00:00:00 2001
From: Jason Molenda <jmolenda at apple.com>
Date: Thu, 22 Aug 2024 18:29:55 -0700
Subject: [PATCH] [lldb] Remove limit on max memory read size

`memory read` will return an error if you try to read more than 1k
bytes in a single command, instructing you to set
`target.max-memory-read-size` or use `--force` if you intended to
read more than that.  This is a safeguard for a command where people
are being explicit about how much memory they would like lldb to
read (either to display, or save to a file) and is an annoyance
every time you need to read more than a small amount.  If someone
confuses the --count argument with the start address, lldb may begin
dumping gigabytes of data but I'd rather that behavior than requiring
everyone to special-case their way around a common use case.
---
 lldb/source/Target/TargetProperties.td | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/lldb/source/Target/TargetProperties.td b/lldb/source/Target/TargetProperties.td
index 7bb5bd53688b14..f553d92f7c64f6 100644
--- a/lldb/source/Target/TargetProperties.td
+++ b/lldb/source/Target/TargetProperties.td
@@ -102,7 +102,7 @@ let Definition = "target" in {
     DefaultUnsignedValue<1024>,
     Desc<"Maximum number of characters to show when using %s in summary strings.">;
   def MaxMemReadSize: Property<"max-memory-read-size", "UInt64">,
-    DefaultUnsignedValue<1024>,
+    DefaultUnsignedValue<4294967295>,
     Desc<"Maximum number of bytes that 'memory read' will fetch before --force must be specified.">;
   def BreakpointUseAvoidList: Property<"breakpoints-use-platform-avoid-list", "Boolean">,
     DefaultTrue,