Declare arrays with different sizes in a C typedef struct
0
I know how to dynamic allocate a new array with malloc.
I wonder if there's a way to avoid that in this situation:
#define RX_BUFFER_SIZE 256
#define TX_BUFFER_SIZE 128
typedef struct MyBuffer
{
volatile uint8_t RX[RX_BUFFER_SIZE];
volatile uint8_t TX[TX_BUFFER_SIZE];
volatile uint16_t RX_Head;
volatile uint16_t RX_Tail;
volatile uint16_t TX_Head;
volatile uint16_t TX_Tail;
} MyBuffer_t;
typedef struct MyChannel
{
// other stuff
MyBuffer_t buffer;
} MyChannel_t;
then in my code I create several variables like this:
MyChannel_t ch1;
MyChannel_t ch2;
MyChannel_t ch3;
but I would like to set a different sizes of the arrays for each variable. It's ok to select among a small set, i.e.:
#define RX_BUFFER_SIZE_S 32
#define TX_BUFFER_SIZE_S 16
#define RX_BUFFER_SIZE_M 128
#define TX_BUFFER_SIZE_M 64
#define RX_BUFFER_SIZE_L 256
#define TX_BUFFER_SIZE_L 128
Is there a way to achieve this without using malloc?
c arrays struct typedef
asked Nov 15 '18 at 9:03
MarkMark
1,10321439
add a comment |
0
I know how to dynamic allocate a new array with malloc.
I wonder if there's a way to avoid that in this situation:
#define RX_BUFFER_SIZE 256
#define TX_BUFFER_SIZE 128
typedef struct MyBuffer
{
volatile uint8_t RX[RX_BUFFER_SIZE];
volatile uint8_t TX[TX_BUFFER_SIZE];
volatile uint16_t RX_Head;
volatile uint16_t RX_Tail;
volatile uint16_t TX_Head;
volatile uint16_t TX_Tail;
} MyBuffer_t;
typedef struct MyChannel
{
// other stuff
MyBuffer_t buffer;
} MyChannel_t;
then in my code I create several variables like this:
MyChannel_t ch1;
MyChannel_t ch2;
MyChannel_t ch3;
but I would like to set a different sizes of the arrays for each variable. It's ok to select among a small set, i.e.:
#define RX_BUFFER_SIZE_S 32
#define TX_BUFFER_SIZE_S 16
#define RX_BUFFER_SIZE_M 128
#define TX_BUFFER_SIZE_M 64
#define RX_BUFFER_SIZE_L 256
#define TX_BUFFER_SIZE_L 128
Is there a way to achieve this without using malloc?
c arrays struct typedef
asked Nov 15 '18 at 9:03
MarkMark
1,10321439
If you would declare the sizes in each source file, then include the typedef, then you can.
– Paul Ogilvie
Nov 15 '18 at 9:08
I would like to set the sizes for eachMyChannel_tdeclared.
– Mark
Nov 15 '18 at 9:09
You can, if you declare them in different source files as per my suggestion. Otherwise, it is not possible.
– Paul Ogilvie
Nov 15 '18 at 9:15
Sidenote: YourMyBuffer_tshould actually be namedMy2Buffers_t. I would recommend having only single buffer, head and tail in the structure, and then create distinct RX and TX instances that same type.
– user694733
Nov 15 '18 at 10:35
add a comment |
0
0
0
I know how to dynamic allocate a new array with malloc.
I wonder if there's a way to avoid that in this situation:
#define RX_BUFFER_SIZE 256
#define TX_BUFFER_SIZE 128
typedef struct MyBuffer
{
volatile uint8_t RX[RX_BUFFER_SIZE];
volatile uint8_t TX[TX_BUFFER_SIZE];
volatile uint16_t RX_Head;
volatile uint16_t RX_Tail;
volatile uint16_t TX_Head;
volatile uint16_t TX_Tail;
} MyBuffer_t;
typedef struct MyChannel
{
// other stuff
MyBuffer_t buffer;
} MyChannel_t;
then in my code I create several variables like this:
MyChannel_t ch1;
MyChannel_t ch2;
MyChannel_t ch3;
but I would like to set a different sizes of the arrays for each variable. It's ok to select among a small set, i.e.:
#define RX_BUFFER_SIZE_S 32
#define TX_BUFFER_SIZE_S 16
#define RX_BUFFER_SIZE_M 128
#define TX_BUFFER_SIZE_M 64
#define RX_BUFFER_SIZE_L 256
#define TX_BUFFER_SIZE_L 128
Is there a way to achieve this without using malloc?
c arrays struct typedef
asked Nov 15 '18 at 9:03
MarkMark
1,10321439
I know how to dynamic allocate a new array with malloc.
I wonder if there's a way to avoid that in this situation:
#define RX_BUFFER_SIZE 256
#define TX_BUFFER_SIZE 128
typedef struct MyBuffer
{
volatile uint8_t RX[RX_BUFFER_SIZE];
volatile uint8_t TX[TX_BUFFER_SIZE];
volatile uint16_t RX_Head;
volatile uint16_t RX_Tail;
volatile uint16_t TX_Head;
volatile uint16_t TX_Tail;
} MyBuffer_t;
typedef struct MyChannel
{
// other stuff
MyBuffer_t buffer;
} MyChannel_t;
then in my code I create several variables like this:
MyChannel_t ch1;
MyChannel_t ch2;
MyChannel_t ch3;
but I would like to set a different sizes of the arrays for each variable. It's ok to select among a small set, i.e.:
#define RX_BUFFER_SIZE_S 32
#define TX_BUFFER_SIZE_S 16
#define RX_BUFFER_SIZE_M 128
#define TX_BUFFER_SIZE_M 64
#define RX_BUFFER_SIZE_L 256
#define TX_BUFFER_SIZE_L 128
Is there a way to achieve this without using malloc?
c arrays struct typedef
c arrays struct typedef
asked Nov 15 '18 at 9:03
MarkMark
1,10321439
asked Nov 15 '18 at 9:03
MarkMark
1,10321439
asked Nov 15 '18 at 9:03
MarkMark
1,10321439
asked Nov 15 '18 at 9:03
MarkMark
1,10321439
asked Nov 15 '18 at 9:03
MarkMark
1,10321439
1,10321439
If you would declare the sizes in each source file, then include the typedef, then you can.
– Paul Ogilvie
Nov 15 '18 at 9:08
I would like to set the sizes for eachMyChannel_tdeclared.
– Mark
Nov 15 '18 at 9:09
You can, if you declare them in different source files as per my suggestion. Otherwise, it is not possible.
– Paul Ogilvie
Nov 15 '18 at 9:15
Sidenote: YourMyBuffer_tshould actually be namedMy2Buffers_t. I would recommend having only single buffer, head and tail in the structure, and then create distinct RX and TX instances that same type.
– user694733
Nov 15 '18 at 10:35
add a comment |
If you would declare the sizes in each source file, then include the typedef, then you can.
– Paul Ogilvie
Nov 15 '18 at 9:08
I would like to set the sizes for eachMyChannel_tdeclared.
– Mark
Nov 15 '18 at 9:09
You can, if you declare them in different source files as per my suggestion. Otherwise, it is not possible.
– Paul Ogilvie
Nov 15 '18 at 9:15
Sidenote: YourMyBuffer_tshould actually be namedMy2Buffers_t. I would recommend having only single buffer, head and tail in the structure, and then create distinct RX and TX instances that same type.
– user694733
Nov 15 '18 at 10:35
If you would declare the sizes in each source file, then include the typedef, then you can.
– Paul Ogilvie
Nov 15 '18 at 9:08
If you would declare the sizes in each source file, then include the typedef, then you can.
– Paul Ogilvie
Nov 15 '18 at 9:08
I would like to set the sizes for each
MyChannel_t declared.– Mark
Nov 15 '18 at 9:09
I would like to set the sizes for each
MyChannel_t declared.– Mark
Nov 15 '18 at 9:09
You can, if you declare them in different source files as per my suggestion. Otherwise, it is not possible.
– Paul Ogilvie
Nov 15 '18 at 9:15
You can, if you declare them in different source files as per my suggestion. Otherwise, it is not possible.
– Paul Ogilvie
Nov 15 '18 at 9:15
Sidenote: Your
MyBuffer_t should actually be named My2Buffers_t. I would recommend having only single buffer, head and tail in the structure, and then create distinct RX and TX instances that same type.– user694733
Nov 15 '18 at 10:35
Sidenote: Your
MyBuffer_t should actually be named My2Buffers_t. I would recommend having only single buffer, head and tail in the structure, and then create distinct RX and TX instances that same type.– user694733
Nov 15 '18 at 10:35
add a comment |
1 Answer
1
active
oldest
votes
2
Declare your buffers as pointers:
typedef struct MyBuffer
{
volatile uint8_t * RX;
volatile uint8_t * TX;
size_t rxSize;
size_t txSize;
volatile uint16_t RX_Head;
...
And then use separate static allocation for the buffers, and use them to initialize your object.
volatile uint8_t ch1_rx_buffer[RX_BUFFER_SIZE_S];
volatile uint8_t ch1_tx_buffer[TX_BUFFER_SIZE_S];
MyChannel_t ch1 = {
.buffer = {
ch1_rx_buffer,
ch1_tx_buffer,
sizeof ch1_rx_buffer,
sizeof ch1_tx_buffer,
...
}
}
answered Nov 15 '18 at 9:11
user694733user694733
11.1k12851
add a comment |
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1 Answer
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1 Answer
1
active
oldest
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active
oldest
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oldest
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2
Declare your buffers as pointers:
typedef struct MyBuffer
{
volatile uint8_t * RX;
volatile uint8_t * TX;
size_t rxSize;
size_t txSize;
volatile uint16_t RX_Head;
...
And then use separate static allocation for the buffers, and use them to initialize your object.
volatile uint8_t ch1_rx_buffer[RX_BUFFER_SIZE_S];
volatile uint8_t ch1_tx_buffer[TX_BUFFER_SIZE_S];
MyChannel_t ch1 = {
.buffer = {
ch1_rx_buffer,
ch1_tx_buffer,
sizeof ch1_rx_buffer,
sizeof ch1_tx_buffer,
...
}
}
answered Nov 15 '18 at 9:11
user694733user694733
11.1k12851
add a comment |
2
Declare your buffers as pointers:
typedef struct MyBuffer
{
volatile uint8_t * RX;
volatile uint8_t * TX;
size_t rxSize;
size_t txSize;
volatile uint16_t RX_Head;
...
And then use separate static allocation for the buffers, and use them to initialize your object.
volatile uint8_t ch1_rx_buffer[RX_BUFFER_SIZE_S];
volatile uint8_t ch1_tx_buffer[TX_BUFFER_SIZE_S];
MyChannel_t ch1 = {
.buffer = {
ch1_rx_buffer,
ch1_tx_buffer,
sizeof ch1_rx_buffer,
sizeof ch1_tx_buffer,
...
}
}
answered Nov 15 '18 at 9:11
user694733user694733
11.1k12851
add a comment |
2
2
2
Declare your buffers as pointers:
typedef struct MyBuffer
{
volatile uint8_t * RX;
volatile uint8_t * TX;
size_t rxSize;
size_t txSize;
volatile uint16_t RX_Head;
...
And then use separate static allocation for the buffers, and use them to initialize your object.
volatile uint8_t ch1_rx_buffer[RX_BUFFER_SIZE_S];
volatile uint8_t ch1_tx_buffer[TX_BUFFER_SIZE_S];
MyChannel_t ch1 = {
.buffer = {
ch1_rx_buffer,
ch1_tx_buffer,
sizeof ch1_rx_buffer,
sizeof ch1_tx_buffer,
...
}
}
answered Nov 15 '18 at 9:11
user694733user694733
11.1k12851
Declare your buffers as pointers:
typedef struct MyBuffer
{
volatile uint8_t * RX;
volatile uint8_t * TX;
size_t rxSize;
size_t txSize;
volatile uint16_t RX_Head;
...
And then use separate static allocation for the buffers, and use them to initialize your object.
volatile uint8_t ch1_rx_buffer[RX_BUFFER_SIZE_S];
volatile uint8_t ch1_tx_buffer[TX_BUFFER_SIZE_S];
MyChannel_t ch1 = {
.buffer = {
ch1_rx_buffer,
ch1_tx_buffer,
sizeof ch1_rx_buffer,
sizeof ch1_tx_buffer,
...
}
}
answered Nov 15 '18 at 9:11
user694733user694733
11.1k12851
edited Nov 15 '18 at 9:16
answered Nov 15 '18 at 9:11
user694733user694733
11.1k12851
answered Nov 15 '18 at 9:11
user694733user694733
11.1k12851
answered Nov 15 '18 at 9:11
user694733user694733
11.1k12851
11.1k12851
add a comment |
add a comment |
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If you would declare the sizes in each source file, then include the typedef, then you can.
– Paul Ogilvie
Nov 15 '18 at 9:08
I would like to set the sizes for each
MyChannel_tdeclared.– Mark
Nov 15 '18 at 9:09
You can, if you declare them in different source files as per my suggestion. Otherwise, it is not possible.
– Paul Ogilvie
Nov 15 '18 at 9:15
Sidenote: Your
MyBuffer_tshould actually be namedMy2Buffers_t. I would recommend having only single buffer, head and tail in the structure, and then create distinct RX and TX instances that same type.– user694733
Nov 15 '18 at 10:35