Show context

[JonathonReinhart]

Show context around matches, like grep. The context should be shown in hex, like the output of hexdump -C.

Complicating factors:

• grep will "combine" overlapping context between matches
• We currently output filename:offset for each match. This might not make sense when showing hex context, because it should be 0x10-aligned.

Perhaps we could output the "found" offsets in the right gutter, comma-separated:

foo.bin:0x0120:  ff ff ff ff ff ff ff ff 11 ff ff ff ff ff 11 ff        0x128, 0x12E

[xrysf03]

I was looking for a binary grep, and of the several bgreps out there, I liked yours best, because it's written in plain C and I like the coding style.
I've cobbled together a simple "context printing" enhancement - I hope you can see the ZIP file attached (tried including the bare patch, but github says "unsupported format" ;-)

bgrep-print-context.patch.zip

The resulting enhanced bgrep has shown to me, that trying to find "in al,dx" (the instruction is a single byte 0xEC) in a large DOS .EXE is not a good idea, as that single byte is fairly commonly used as a stack offset in function argument passing (argument 14 bytes down from the Base Pointer). Ahh well :-) Floating between DosBox with heavy debug and IDA Free 4.9...

[JonathonReinhart]

@xrysf03 Thanks for the patch. Next time, you should try sending a pull request!

I didn't use your code, but it inspired me to implement #23. What do you think?