In one project I have many quasi-fixed strings that I'd like to keep in non volatile memory (Flash) to avoid losing precious RAM space.
static const char s1 = "/my/very/long/string/of/01020304"; static const char s2 = "/another/string/01020304"; ...
Substring "01020304" is a serial number that changes during production with specific device. It has the same length in bytes (it's a simple hex representation of a 32-bits integer).
Of course it's too difficult and slow to rebuild the firmware during production passing to the compiler the real serial number. I think a better solution is to patch the .hex file generated by the compiler.
I'm wondering how to detect the exact positions (addresses) of serial numbers to fix.
The build system is gcc, so I could search for s1 in the elf file. Do you know of a tool that returns the address of a symbol in the elf or map file?
Could you suggest a better approach?