diff options
Diffstat (limited to 'client/examples/puzbus-hello-world.cpp')
-rw-r--r-- | client/examples/puzbus-hello-world.cpp | 67 |
1 files changed, 67 insertions, 0 deletions
diff --git a/client/examples/puzbus-hello-world.cpp b/client/examples/puzbus-hello-world.cpp new file mode 100644 index 0000000..dcc965b --- /dev/null +++ b/client/examples/puzbus-hello-world.cpp @@ -0,0 +1,67 @@ +#include <cstdio> +#include <cstdlib> +#include <cstring> +#include <unistd.h> + +#include "puzbusv1.h" + +int send_message() { + const char* data = "Test message data!"; + struct pb_msg output = { + .addr = 0x39, + .data = (char*) data, + .length = strlen(data), + }; + + char* packed; + size_t size; + if (!pb_write(&output, &packed, &size)) { + printf("error writing!\n"); + return EXIT_FAILURE; + } + + fwrite(packed, sizeof(packed[0]), size, stdout); + fflush(stdout); + + return EXIT_SUCCESS; +} + +int read_message() { + freopen(NULL, "rb", stdin); // allow binary on stdin + struct pb_msg input; + + char buf[4]; // extremely small buffer to test chunked message parsing + size_t bytes = 0; + + while ((bytes = fread(buf, sizeof(buf[0]), sizeof(buf), stdin)) > 0) { + int ret = pb_read(&input, buf, bytes); + + // header read error + if (ret < 0) { + printf("error reading!\n"); + return EXIT_FAILURE; + } + + // continue reading if more bytes needed... + if (ret > 0) continue; + + // message read completely! + printf("address: 0x%02x\n", input.addr); + printf("data: \"%.*s\"\n", input.length, input.data); + free(input.data); + return EXIT_SUCCESS; + } + + // if we reach this point, data was read but it did not contain a complete + // message, and is thus considered a failure + return EXIT_FAILURE; +} + +int main() { + if (!isatty(fileno(stdout))) return send_message(); + if (!isatty(fileno(stdin))) return read_message(); + + printf("please pipe some data in or out to use this program\n"); + return EXIT_SUCCESS; +} + |