[flashrom-gerrit] Change in flashrom[master]: [FIX ME] tests: Add test for extract operation

[Anastasia Klimchuk (Code Review)]

Attention is currently required from: Edward O'Callaghan, Daniel Campello.
Anastasia Klimchuk has posted comments on this change. ( https://review.coreboot.org/c/flashrom/+/59532 )

Change subject: [FIX ME] tests: Add test for extract operation
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Patch Set 1:

(1 comment)

Patchset:

PS1: 
Daniel, Edward I added you because I found your names in commit ce983bccaab450d358854494f15c2d8a1846d56b which added do_extract operation.

I am confused because it seems do_extract operation always returns 1. This is because:

1) do_extract calls `do_read(flash, NULL)` and so at this point filename is NULL
2) do_read calls `read_flash_to_file(flash, filename)`
3) then it goes to `write_buf_to_file(buf, size, filename)`
and the latter has a block of code:
 if (!filename) {
   msg_gerr("No filename specified.\n");
   return 1;
 }

There is no way to provide filename into do_extract, so I don't know how to make it work. I would appreciate your advice!

As an experiment, I changes two lines in flashrom.c#do_extract:
replaced
 return do_read(flash, NULL);

with
 const char *const filename = "read_chip.test";
 return do_read(flash, filename);

This replacement makes test running successfully!

Maybe I am using API in a wrong way? Or could it be bug in do_extract?

Thank you for advice!