ardupilot/libraries/AP_Common/ExpandingString.h

64 lines
1.7 KiB
C
Raw Normal View History

/*
This program is free software: you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation, either version 3 of the License, or
(at your option) any later version.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
/*
expanding string for easy construction of text buffers
*/
#pragma once
#include <AP_HAL/AP_HAL.h>
class ExpandingString {
public:
const char *get_string(void) const {
return buf;
}
uint32_t get_length(void) const {
return used;
}
char *get_writeable_string(void) const {
return buf;
}
// print into the string
void printf(const char *format, ...) FMT_PRINTF(2,3);
// append data to the string. s can be null for zero fill
bool append(const char *s, uint32_t len);
// set address to custom external buffer
void set_buffer(char *s, uint32_t total_len, uint32_t used_len);
// zero out the string
void reset() { used = 0; }
// destructor
~ExpandingString();
bool has_failed_allocation() const {
return allocation_failed;
}
private:
char *buf;
uint32_t buflen;
uint32_t used;
bool allocation_failed;
bool external_buffer;
// try to expand the buffer
bool expand(uint32_t min_needed) WARN_IF_UNUSED;
};