Cast variable type based on format identifier #113
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source/core_mqtt.c
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| @@ -605,7 +605,7 @@ static int32_t sendPacket( MQTTContext_t * pContext, | |||
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| if( bytesSent < 0 ) | |||
| { | |||
| LogError( ( "Transport send failed. Error code=%d.", bytesSent ) ); | |||
| LogError( ( "Transport send failed. Error code=%d.", ( int ) bytesSent ) ); | |||
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Looks like bytesSent is an int32. For the particular case which started this, the message was
format '%d' expects argument of type 'int', but argument 4 has type 'int32_t' {aka 'long int'}
I believe we want to use %ld and cast to long to handle the case where int is smaller that 32 bits.
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Good catch. I'll cast int32_t to long int and int16_t to int.
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Why cast int16_t to int? A short is guaranteed to be at least 2 bytes.
Nit: long int and long are identical, I think we've been leaving off the int in other places where it's not necessary
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Oh yeah. I think I just wanted to err on the side of caution, but I didn't end up casting any int16_t types anyway.
source/core_mqtt.c
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| LogError( ( "Failed to update state of publish %u.", | ||
| ( unsigned int ) packetId ) ); |
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Since this is originally a uint16_t, should we use unsigned short?
| LogError( ( "Failed to update state of publish %u.", | |
| ( unsigned int ) packetId ) ); | |
| LogError( ( "Failed to update state of publish %hu.", | |
| ( unsigned short ) packetId ) ); |
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I think the definition of short is really dependent on the compiler, so I wanted to err on the side of caution. Although, we use short in other places for 16-bit data types, so I have updated it.
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An unsigned short is required to be able to hold values up to 65,535, according to 5.2.4.2
Only ever use base format specifiers and always cast to the standard C type