pkg,service: add cmd `examinemem`(`x`) for examining memory. #1814

chainhelen · 2020-01-07T07:09:07Z

According to #1800 #1584 #1038, dlv should enable the user to dive into
memory. User can print binary data in specific memory address range.
But not support for sepecific variable name or structures temporarily.(Because
I have no idea that modify print command.)

Close #1584.

Next some questions:

support the format for printcmd, include address , variable name and structures(no idea).
support the form about t(binary), f(float), a(address), i(instruction), c(char), s(string) .
support the negative position from address. (This is why also use x /<FMT> [address] like gdb, but not x -<FMT> [address]).

I can close this pr if you against.

aarzilli · 2020-01-07T07:58:10Z

See test failures.

chainhelen · 2020-01-07T13:31:41Z

Sorry for test failures of docs, I have done.
(Something faield with others now, not involved with this pr.)

aarzilli

@derekparker what do you think of the design of this command?

service/debugger/debugger.go

service/rpc2/server.go

pkg/terminal/command.go

derekparker

First pass finished. I'm excited for this command, thanks for sending in this patch!

derekparker · 2020-01-11T20:14:11Z

service/debugger/debugger.go

@@ -1310,6 +1310,23 @@ func (d *Debugger) ListDynamicLibraries() []api.Image {
 	return r
 }

+// ExamineMemory returns a list of specific address memory that len is num.


This comment should be rewritten to something like: ExamineMemory returns the raw memory stored at the given address. The amount of data to be read is specified by length. This function will return an error if it reads less than ``length`` bytes.

derekparker · 2020-01-11T20:17:23Z

service/debugger/debugger.go

@@ -1310,6 +1310,23 @@ func (d *Debugger) ListDynamicLibraries() []api.Image {
 	return r
 }

+// ExamineMemory returns a list of specific address memory that len is num.
+func (d *Debugger) ExamineMemory(address uintptr, count int) ([]byte, error) {


s/count/length/ .. I think we use size internally in proc/mem.go as well, but I think either works a bit btter than count.

derekparker · 2020-01-11T20:18:27Z

service/debugger/debugger.go

+
+	thread := d.target.CurrentThread()
+	data := make([]byte, count)
+	rn, err := thread.ReadMemory(data, address)


s/rn/read/ for a bit more descriptive name.

derekparker · 2020-01-11T20:34:15Z

pkg/terminal/command.go

+	}
+	i := 1
+	for ; i < len(fmtStr); i++ {
+		if fmtStr[i] < '0' || fmtStr[i] > '9' {


Could use unicode.IsDigit here.

derekparker · 2020-01-11T20:49:32Z

pkg/terminal/command.go

@@ -368,6 +369,19 @@ Defines <alias> as an alias to <command> or removes an alias.`},

 If locspec is omitted edit will open the current source file in the editor, otherwise it will open the specified location.`},
 		{aliases: []string{"libraries"}, cmdFn: libraries, helpMsg: `List loaded dynamic libraries`},
+
+		{aliases: []string{"examinemem", "x"}, cmdFn: examineMemoryCmd, helpMsg: `Examine memory: examinemem [-<fmt>] <address>.
+	Fmt is a count followed by a format letter and a size letter.


I wonder if we could just simplify this. Do we really need to specify byte vs halfword vs word etc...?

I'm leaning towards not giving control over chunk size and simply having flags for -len and -fmt. Length is always in bytes and maybe defaults to the arch pointer size and fmt defaults to hex.

Oh, thx for your guidance. I get something, and need some time to change it.

chainhelen · 2020-01-17T09:19:48Z

Examine memory:

examinemem [-fmt <format>] [-len <length>] <address>

Format represents the data format and the value is one of this list (default hex): oct(octal), hex(hexadecimal), dec(decimal), bin(binary).
Length is the number of bytes (default 1), please ensure len is not more than 1k.
Address is the memory location of the target to examine.
For example: x -fmt hex -len 20 0xc00008af38

Has done and rebase , please check it again. Thx.

chainhelen · 2020-01-17T09:26:43Z

~~Sorry for ci failed, it is because I add binary format. It looks diffrent versions of golang output this differently. I will fix it.~~

Has fixed, please check above description and code again . Thx.

pkg/terminal/command.go

aarzilli · 2020-01-17T15:12:35Z

pkg/terminal/command.go

+
+	// TODO, maybe configured by user.
+	if length > 1000 {
+		return fmt.Errorf("len must be not more than 1k")


"len must be less than 1000"

@aarzilli I use not more than because length belong to [1, 1000] instead of [1, 1000).
So maybe "len must be less than or equal to 1000“ better, what's your opinion?

service/api/prettyprint.go

aarzilli · 2020-01-17T15:17:09Z

service/api/prettyprint.go

+		for j := 0; j < cols && i*cols+j < l; j++ {
+			curOutput := fmt.Sprintf(colFormat, res[i*cols+j])
+
+			// Diffrent versions of golang output differently if binanry.


s/binanry/binary/

pkg/terminal/command.go

aarzilli · 2020-01-18T16:28:30Z

pkg/terminal/command.go

+			}
+		default:
+			if i != len(v)-1 {
+				return fmt.Errorf("wrong arguments for input")


fmt.Errorf("unknown option %q", v[i])

pkg/terminal/command.go

service/api/prettyprint.go

According to go-delve#1800 go-delve#1584 go-delve#1038, `dlv` should enable the user to dive into memory. User can print binary data in specific memory address range. But not support for sepecific variable name or structures temporarily.(Because I have no idea that modify `print` command.) Close go-delve#1584.

aarzilli

LGTM, thank you.

hengwu0 · 2020-01-26T09:06:28Z

support the format for printcmd, include address , variable name and structures(no idea).

If you are investigativing, please fix this error:

jim@localhost:~/test$ dlv exec ./A
Type 'help' for list of commands.
(dlv) p 123//9
123
(dlv)

The Exp:123//9 should be en error actually.

chainhelen · 2020-01-27T08:44:17Z

support the format for printcmd, include address , variable name and structures(no idea).

If you are investigativing, please fix this error:
jim@localhost:~/test$ dlv exec ./A
Type 'help' for list of commands.
(dlv) p 123//9
123
(dlv)
The Exp:123//9 should be en error actually.

I will do my best.

derekparker

LGTM

1. Don't use intelligent '#' in fmt of go because it is not always satisfying for diffrent version of golang. Always keep one leading zero for octal and one leading '0x' for hex manually. Then keep alignment for every byte. 2. Always keep addr alignment when the lens of two adjacent address are different. Update go-delve#1814.

1. Don't use intelligent '#' in fmt of go because it is not always satisfying for diffrent version of golang. Always keep one leading zero for octal and one leading '0x' for hex manually. Then keep alignment for every byte. 2. Always keep addr alignment when the lens of two adjacent address are different. Update #1814.

hitzhangjie · 2020-08-22T11:43:45Z

Hi, how to enable this command ? I didn't see it in the help command list.

Is there some buildtags?

Ah, I run go get command with the wrong package path before, after update the dlv, I can use x now.

…e#1814) According to go-delve#1800 go-delve#1584 go-delve#1038, `dlv` should enable the user to dive into memory. User can print binary data in specific memory address range. But not support for sepecific variable name or structures temporarily.(Because I have no idea that modify `print` command.) Close go-delve#1584.

…#1888) 1. Don't use intelligent '#' in fmt of go because it is not always satisfying for diffrent version of golang. Always keep one leading zero for octal and one leading '0x' for hex manually. Then keep alignment for every byte. 2. Always keep addr alignment when the lens of two adjacent address are different. Update go-delve#1814.

…e#1814) According to go-delve#1800 go-delve#1584 go-delve#1038, `dlv` should enable the user to dive into memory. User can print binary data in specific memory address range. But not support for sepecific variable name or structures temporarily.(Because I have no idea that modify `print` command.) Close go-delve#1584.

…#1888) 1. Don't use intelligent '#' in fmt of go because it is not always satisfying for diffrent version of golang. Always keep one leading zero for octal and one leading '0x' for hex manually. Then keep alignment for every byte. 2. Always keep addr alignment when the lens of two adjacent address are different. Update go-delve#1814.

chainhelen force-pushed the examinememory branch from 84c1372 to 9c8bf7b Compare January 7, 2020 07:25

chainhelen force-pushed the examinememory branch from 9c8bf7b to 8faf78d Compare January 7, 2020 08:17

chainhelen mentioned this pull request Jan 7, 2020

proc_test,command_test: rename math.go into mathematics.go #1816

Closed

aarzilli reviewed Jan 9, 2020

View reviewed changes

chainhelen force-pushed the examinememory branch 2 times, most recently from cd16205 to 69bb0f8 Compare January 9, 2020 13:19

derekparker requested changes Jan 11, 2020

View reviewed changes

chainhelen force-pushed the examinememory branch from 69bb0f8 to 0d896b7 Compare January 17, 2020 09:15

chainhelen force-pushed the examinememory branch 4 times, most recently from 5cd7aac to 34d9135 Compare January 17, 2020 13:02

aarzilli reviewed Jan 17, 2020

View reviewed changes

chainhelen changed the title ~~pkg,service: add cmd x for examining memory.~~ pkg,service: add cmd examinemem(x) for examining memory. Jan 17, 2020

chainhelen force-pushed the examinememory branch 2 times, most recently from 7d4d7e0 to 125e282 Compare January 17, 2020 19:21

aarzilli reviewed Jan 18, 2020

View reviewed changes

chainhelen force-pushed the examinememory branch from 125e282 to 23a6700 Compare January 19, 2020 04:02

aarzilli approved these changes Jan 19, 2020

View reviewed changes

derekparker approved these changes Feb 13, 2020

View reviewed changes

derekparker merged commit a5d9dbe into go-delve:master Feb 13, 2020

chainhelen mentioned this pull request Feb 24, 2020

pkg,service: Optimized the display of examinemem command. #1888

Merged

Provide feedback

Saved searches

Use saved searches to filter your results more quickly

pkg,service: add cmd `examinemem`(`x`) for examining memory. #1814

pkg,service: add cmd `examinemem`(`x`) for examining memory. #1814

chainhelen commented Jan 7, 2020

aarzilli commented Jan 7, 2020

chainhelen commented Jan 7, 2020

aarzilli left a comment

derekparker left a comment

derekparker Jan 11, 2020

derekparker Jan 11, 2020

derekparker Jan 11, 2020

derekparker Jan 11, 2020

derekparker Jan 11, 2020

chainhelen Jan 12, 2020

chainhelen commented Jan 17, 2020

chainhelen commented Jan 17, 2020 •

edited

Loading

aarzilli Jan 17, 2020

chainhelen Jan 17, 2020 •

edited

Loading

aarzilli Jan 17, 2020

aarzilli Jan 18, 2020

aarzilli left a comment

hengwu0 commented Jan 26, 2020

chainhelen commented Jan 27, 2020

derekparker left a comment

hitzhangjie commented Aug 22, 2020 •

edited

Loading

pkg,service: add cmd examinemem(x) for examining memory. #1814

pkg,service: add cmd examinemem(x) for examining memory. #1814

Conversation

chainhelen commented Jan 7, 2020

aarzilli commented Jan 7, 2020

chainhelen commented Jan 7, 2020

aarzilli left a comment

Choose a reason for hiding this comment

derekparker left a comment

Choose a reason for hiding this comment

Choose a reason for hiding this comment

Choose a reason for hiding this comment

Choose a reason for hiding this comment

Choose a reason for hiding this comment

Choose a reason for hiding this comment

Choose a reason for hiding this comment

chainhelen commented Jan 17, 2020

chainhelen commented Jan 17, 2020 • edited Loading

Choose a reason for hiding this comment

chainhelen Jan 17, 2020 • edited Loading

Choose a reason for hiding this comment

Choose a reason for hiding this comment

Choose a reason for hiding this comment

aarzilli left a comment

Choose a reason for hiding this comment

hengwu0 commented Jan 26, 2020

chainhelen commented Jan 27, 2020

derekparker left a comment

Choose a reason for hiding this comment

hitzhangjie commented Aug 22, 2020 • edited Loading

pkg,service: add cmd `examinemem`(`x`) for examining memory. #1814

pkg,service: add cmd `examinemem`(`x`) for examining memory. #1814

chainhelen commented Jan 17, 2020 •

edited

Loading

chainhelen Jan 17, 2020 •

edited

Loading

hitzhangjie commented Aug 22, 2020 •

edited

Loading