Error on big endian machine

[nnllyy]

The following structures cannot use memcpy

mqtt_msg.h

typedef struct {
uint8_t bit_0 : 1;
uint8_t bit_1 : 1;
uint8_t bit_2 : 1;
uint8_t bit_3 : 1;
uint8_t packet_type : 4;
} mqtt_common_hdr;

typedef struct {
uint8_t retain : 1;
uint8_t qos : 2;
uint8_t dup : 1;
uint8_t packet_type : 4;
} mqtt_pub_hdr;

[xinyi-xs]

I'm sorry, but I'm having trouble understanding whether you're asking about copying data between a buffer and a struct, or between two structs. Could you please clarify which scenario you're referring to?

[nnllyy]

This structure should be defined in this way At 2023-05-17 17:30:34, "xinyi" ***@***.***> wrote: I'm sorry, but I'm having trouble understanding whether you're asking about copying data between a buffer and a struct, or between two structs. Could you please clarify which scenario you're referring to? — Reply to this email directly, view it on GitHub, or unsubscribe. You are receiving this because you authored the thread.Message ID: ***@***.***>

[nnllyy]

Index: CMakeLists.txt ===================================================================

…

--- CMakeLists.txt +++ CMakeLists.txt @@ -145,6 +145,12 @@ set(NNG_SANITIZER_FLAGS "-fsanitize=${NNG_SANITIZER}") endif () +include(TestBigEndian) +test_big_endian(NNG_BIG_ENDIAN) +if (NNG_BIG_ENDIAN) + add_definitions(-DNNG_BIG_ENDIAN) +endif () + if (NNG_ENABLE_COVERAGE) # NB: This only works for GCC and Clang 3.0 and newer. If your stuff # is older than that, you will need to find something newer. For Index: src/supplemental/mqtt/mqtt_msg.h ===================================================================

--- src/supplemental/mqtt/mqtt_msg.h(版本 1888) +++ src/supplemental/mqtt/mqtt_msg.h(版本 1889) @@ -55,7 +55,16 @@ /* CONNECT flags */ typedef struct conn_flags_t { +#ifdef NNG_BIG_ENDIAN +uint8_t username_flag : 1; +uint8_t password_flag : 1; +uint8_t will_retain : 1; +uint8_t will_qos : 2; +uint8_t will_flag : 1; +uint8_t clean_session : 1; uint8_t reserved : 1; +#else +uint8_t reserved : 1; uint8_t clean_session : 1; uint8_t will_flag : 1; uint8_t will_qos : 2; @@ -62,6 +71,7 @@ uint8_t will_retain : 1; uint8_t password_flag : 1; uint8_t username_flag : 1; +#endif } conn_flags; /***************************************************************************** @@ -211,18 +221,33 @@ }; typedef struct { +#ifdef NNG_BIG_ENDIAN +uint8_t packet_type : 4; +uint8_t bit_3 : 1; +uint8_t bit_2 : 1; +uint8_t bit_1 : 1; uint8_t bit_0 : 1; +#else +uint8_t bit_0 : 1; uint8_t bit_1 : 1; uint8_t bit_2 : 1; uint8_t bit_3 : 1; uint8_t packet_type : 4; +#endif } mqtt_common_hdr; typedef struct { +#ifdef NNG_BIG_ENDIAN +uint8_t packet_type : 4; +uint8_t dup : 1; +uint8_t qos : 2; uint8_t retain : 1; +#else +uint8_t retain : 1; uint8_t qos : 2; uint8_t dup : 1; uint8_t packet_type : 4; +#endif } mqtt_pub_hdr; typedef struct mqtt_fixed_hdr_t { At 2023-05-17 17:30:34, "xinyi" ***@***.***> wrote: I'm sorry, but I'm having trouble understanding whether you're asking about copying data between a buffer and a struct, or between two structs. Could you please clarify which scenario you're referring to? — Reply to this email directly, view it on GitHub, or unsubscribe. You are receiving this because you authored the thread.Message ID: ***@***.***>

[xinyi-xs]

@nnllyy thanks for your advice, I will try it.

[xinyi-xs]

Hi @nnllyy, I wanted to thank you for your advice. I've implemented the struct with bit-field endian-independent, but I haven't tested it on a big endian machine yet. Would you be able to test it on your machine and provide some feedback?

[nnllyy]

Hi @nnllyy, I wanted to thank you for your advice. I've implemented the struct with bit-field endian-independent, but I haven't tested it on a big endian machine yet. Would you be able to test it on your machine and provide some feedback?

My machine is a router and requires cross compilation to run. You can push it and I will test it again

[JaylinYu]

is that router an OpenWRT on MIPS ?