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#include "prism/util/pm_buffer.h"
/**
* Return the size of the pm_buffer_t struct.
*/
size_t
pm_buffer_sizeof(void) {
return sizeof(pm_buffer_t);
}
/**
* Initialize a pm_buffer_t with the given capacity.
*/
bool
pm_buffer_init_capacity(pm_buffer_t *buffer, size_t capacity) {
buffer->length = 0;
buffer->capacity = capacity;
buffer->value = (char *) malloc(capacity);
return buffer->value != NULL;
}
/**
* Initialize a pm_buffer_t with its default values.
*/
bool
pm_buffer_init(pm_buffer_t *buffer) {
return pm_buffer_init_capacity(buffer, 1024);
}
/**
* Return the value of the buffer.
*/
char *
pm_buffer_value(pm_buffer_t *buffer) {
return buffer->value;
}
/**
* Return the length of the buffer.
*/
size_t
pm_buffer_length(pm_buffer_t *buffer) {
return buffer->length;
}
/**
* Append the given amount of space to the buffer.
*/
static inline void
pm_buffer_append_length(pm_buffer_t *buffer, size_t length) {
size_t next_length = buffer->length + length;
if (next_length > buffer->capacity) {
if (buffer->capacity == 0) {
buffer->capacity = 1;
}
while (next_length > buffer->capacity) {
buffer->capacity *= 2;
}
buffer->value = realloc(buffer->value, buffer->capacity);
}
buffer->length = next_length;
}
/**
* Append a generic pointer to memory to the buffer.
*/
static inline void
pm_buffer_append(pm_buffer_t *buffer, const void *source, size_t length) {
size_t cursor = buffer->length;
pm_buffer_append_length(buffer, length);
memcpy(buffer->value + cursor, source, length);
}
/**
* Append the given amount of space as zeroes to the buffer.
*/
void
pm_buffer_append_zeroes(pm_buffer_t *buffer, size_t length) {
size_t cursor = buffer->length;
pm_buffer_append_length(buffer, length);
memset(buffer->value + cursor, 0, length);
}
/**
* Append a formatted string to the buffer.
*/
void
pm_buffer_append_format(pm_buffer_t *buffer, const char *format, ...) {
va_list arguments;
va_start(arguments, format);
int result = vsnprintf(NULL, 0, format, arguments);
va_end(arguments);
if (result < 0) return;
size_t length = (size_t) (result + 1);
size_t cursor = buffer->length;
pm_buffer_append_length(buffer, length);
va_start(arguments, format);
vsnprintf(buffer->value + cursor, length, format, arguments);
va_end(arguments);
buffer->length--;
}
/**
* Append a string to the buffer.
*/
void
pm_buffer_append_string(pm_buffer_t *buffer, const char *value, size_t length) {
pm_buffer_append(buffer, value, length);
}
/**
* Append a list of bytes to the buffer.
*/
void
pm_buffer_append_bytes(pm_buffer_t *buffer, const uint8_t *value, size_t length) {
pm_buffer_append(buffer, (const char *) value, length);
}
/**
* Append a single byte to the buffer.
*/
void
pm_buffer_append_byte(pm_buffer_t *buffer, uint8_t value) {
const void *source = &value;
pm_buffer_append(buffer, source, sizeof(uint8_t));
}
/**
* Append a 32-bit unsigned integer to the buffer as a variable-length integer.
*/
void
pm_buffer_append_varuint(pm_buffer_t *buffer, uint32_t value) {
if (value < 128) {
pm_buffer_append_byte(buffer, (uint8_t) value);
} else {
uint32_t n = value;
while (n >= 128) {
pm_buffer_append_byte(buffer, (uint8_t) (n | 128));
n >>= 7;
}
pm_buffer_append_byte(buffer, (uint8_t) n);
}
}
/**
* Append a 32-bit signed integer to the buffer as a variable-length integer.
*/
void
pm_buffer_append_varsint(pm_buffer_t *buffer, int32_t value) {
uint32_t unsigned_int = ((uint32_t)(value) << 1) ^ ((uint32_t)(value >> 31));
pm_buffer_append_varuint(buffer, unsigned_int);
}
/**
* Concatenate one buffer onto another.
*/
void
pm_buffer_concat(pm_buffer_t *destination, const pm_buffer_t *source) {
if (source->length > 0) {
pm_buffer_append(destination, source->value, source->length);
}
}
/**
* Free the memory associated with the buffer.
*/
void
pm_buffer_free(pm_buffer_t *buffer) {
free(buffer->value);
}
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