Improve wificfg #732
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Without these, wificfg.h can fail to compile because types like uint32_t, size_t or ssize_t are not available.
FreeRTOS/Source/include/FreeRTOSConfig.h makes sure configUSE_TRACE_FACILITY is always defined. But it's defined to 0 when TRACE_FACILITY is disabled. When #ifdef is used, the guarded blocks of code are always compiled and this results in link failure when TRACE_FACILITY is in fact not enabled.
wificfg.c defines the default values for ssid, password and hostname. But because these are not weak, trying to redefine these causes a link error. This change marks the definitions in wificfg.c weak, thus making it possible for a program using the wificfg component to redefine these w/o having to touch wificfg.c.
| const char *wificfg_default_hostname = "eor-%02x%02x%02x"; | ||
| const char *wificfg_default_ssid __attribute__ ((weak)) = "EOR_%02X%02X%02X"; | ||
| const char *wificfg_default_password __attribute__ ((weak)) = "esp-open-rtos"; | ||
| const char *wificfg_default_hostname __attribute__ ((weak)) = "eor-%02x%02x%02x"; |
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These don't need to be 'weak', they are variables that can be trivially modified, just set them in your app initialization code.
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You are right. I didn't realize it's a const char*, not a const char[].
I was motivated by several things:
- I thought I can't really change it (which was wrong)
- I didn't want the literals from the wificfg.c to be present in the binary at all (just a few bytes, but still needless if I'm using my own strings)
- when re-defining a weak symbol, there is no need to do anything at runtime, linker just handles that (yes, just 3 assignments, but when just a declaration can suffice, it seems nicer)
Because the type is const char*, even the second point was not fulfilled. If the type is changed to const char[], then it seems to do what I wanted.
What do you think about keeping these weak and making them const char[]? Or are the last two points from the list above not interesting to you?
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| #ifdef configUSE_TRACE_FACILITY | ||
| #if configUSE_TRACE_FACILITY |
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Yes, that looks right, thanks.
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Several small improvements of extras/wificfg: