httpd_req_get_hdr_value_str() fails to find a field key after an empty value (IDFGH-1539)

[yappy]

Environment

• IDF version (run git describe --tags to find it):
  v3.2
• Build System: Make
• Compiler version (run xtensa-esp32-elf-gcc --version to find it):
  1.22.0-80-g6c4433a
• Operating System: Windows (WSL)
• Power Supply: USB

Problem Description

When there is an empty value entry in HTTP header, httpd_req_get_hdr_value_str() returns ESP_ERR_NOT_FOUND.

Content-Type:<space><cr><lf>
X-FILE-NAME:<space>index.lua<cr><lf>

CANNOT find X-FILE-NAME
If Content-Type is not empty (e.g. image/jpeg) , it succeeds.

Expected Behavior

httpd_req_get_hdr_value_str() succeeds and returns its value. (index.lua)

Actual Behavior

httpd_req_get_hdr_value_str() returns ESP_ERR_NOT_FOUND.

Steps to repropduce

Code to reproduce this issue

const uint32_t HTTP_FILE_NAME_MAX = 32;
char name[HTTP_FILE_NAME_MAX];
ret = httpd_req_get_hdr_value_str(req, "X-FILE-NAME", name, sizeof(name));

[anurag-kar]

@yappy Thanks for reporting the issue. This patch should fix it. Let me know if it works for you. In the meanwhile we'll try to merge the bugfix as soon as possible.

[yappy]

Thank you very much!
It works in my app. It is not urgent for me because there is a workaround (set a non-empty value on the client side) for it.

[yappy]

Any update on this?