Function string_appendf

src/butil/string_printf.cpp:121–127

Basic declarations; allow for parameters of strings and string pieces to be specified.

// Basic declarations; allow for parameters of strings and string
// pieces to be specified.
int string_appendf(std::string* output, const char* format, ...) {
    va_list ap;
    va_start(ap, format);
    const int rc = string_vappendf(output, format, ap);
    va_end(ap);
    return rc;
}

int string_vappendf(std::string* output, const char* format, va_list args) {
    const size_t old_size = output->size();