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Refactored parse_num and parse_type to return type parse_result

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This commit is contained in:
Andreas Tsouchlos 2021-11-18 23:53:15 +01:00
parent 83332cc295
commit f1952186e0
4 changed files with 91 additions and 49 deletions
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11
inc/Logger.h
View File

@ -35,14 +35,11 @@ public:
}
template <detail::ConstString msg, typename... args_t>
void log(args_t...) {
constexpr int len = get_output_len(msg);
static_assert(len > 0, "Syntax error in log string");
void log(args_t... args) {
const auto formatted_msg = format<msg>(args...);
std::cout << "Computed Length: " << len << std::endl;
for (unsigned i = 0; i < msg.size(); ++i) {
m_output_policy.write(msg[i]);
for (const auto& c : formatted_msg) {
m_output_policy.write(c);
}
}

119
inc/parsing.h
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@ -8,6 +8,24 @@
namespace detail {
/*
*
* Parse format string
*
*/
template <typename result_t>
struct parse_result {
bool valid = false;
unsigned new_index = 0;
unsigned length = 0;
result_t result;
};
enum class FormatType { s, c, b, B, d, o, x, X, a, A, e, E, f, F, g, G, p };
// clang-format off
/*
@ -45,74 +63,87 @@ constexpr bool is_digit(ConstString<N> s, unsigned i) {
return (s[i] > 47) && (s[i] < 58);
}
/*
*
* Functions to convert X to char array
* and ConstString to X
*
*/
template <std::size_t N>
constexpr std::pair<unsigned, int> parse_number(ConstString<N> s, unsigned i) {
constexpr parse_result<int> parse_number(ConstString<N> s, unsigned i) {
int number = 0;
while ((i < s.size()) && is_digit(s, i)) {
number = number * 10;
number += (s[i] - 48);
++i;
}
return {i, 0};
return {true, i, 0, number};
}
template <std::size_t N>
constexpr std::pair<unsigned, int> parse_type(ConstString<N> s, unsigned i) {
constexpr parse_result<FormatType> parse_type(ConstString<N> s, unsigned i) {
if (s[i] == 's') { // string
++i;
return {i, 0};
return {true, i, 1, FormatType::s};
} else if (s[i] == 'c') { // char
++i;
return {i, 0};
return {true, i, 1, FormatType::c};
} else if (s[i] == 'b') { // int
++i;
return {i, 0};
return {true, i, 1, FormatType::b};
} else if (s[i] == 'B') {
++i;
return {i, 0};
} else if (s[i] == 'c') {
++i;
return {i, 0};
return {true, i, 1, FormatType::B};
// } else if (s[i] == 'c') {
// ++i;
// return {true, i, 1, FormatType::c};
} else if (s[i] == 'd') {
++i;
return {i, 0};
} else if (s[i] == '0') {
return {true, i, 1, FormatType::d};
} else if (s[i] == 'o') {
++i;
return {i, 0};
return {true, i, 1, FormatType::o};
} else if (s[i] == 'x') {
++i;
return {i, 0};
return {true, i, 1, FormatType::x};
} else if (s[i] == 'X') {
++i;
return {i, 0};
return {true, i, 1, FormatType::X};
} else if (s[i] == 'a') { // float
++i;
return {i, 0};
return {true, i, 1, FormatType::a};
} else if (s[i] == 'A') {
++i;
return {i, 0};
return {true, i, 1, FormatType::A};
} else if (s[i] == 'e') {
++i;
return {i, 0};
return {true, i, 1, FormatType::e};
} else if (s[i] == 'E') {
++i;
return {i, 0};
return {true, i, 1, FormatType::E};
} else if (s[i] == 'f') {
++i;
return {i, 0};
return {true, i, 1, FormatType::f};
} else if (s[i] == 'F') {
++i;
return {i, 0};
return {true, i, 1, FormatType::F};
} else if (s[i] == 'g') {
++i;
return {i, 0};
return {true, i, 1, FormatType::g};
} else if (s[i] == 'G') {
++i;
return {i, 0};
return {true, i, 1, FormatType::G};
} else if (s[i] == 'p') { // pointer
++i;
return {i, 0};
return {true, i, 1, FormatType::p};
}
return {i, -1};
return {false, i, 0, FormatType::a};
}
template <std::size_t N>
@ -124,28 +155,25 @@ constexpr std::pair<unsigned, int> parse_fmt_string(ConstString<N> s,
++i;
if (is_digit(s, i)) {
auto [new_i, extra_len] = parse_number(s, i);
if (extra_len < 0)
return {i, -1};
auto [is_valid, new_i, len, number] = parse_number(s, i);
if (!is_valid) return {i, -1};
i = new_i;
result_extra_len += extra_len;
result_extra_len += number;
}
if (s[i] == '.') {
++i;
auto [new_i, extra_len] = parse_number(s, i);
if (extra_len < 0)
return {i, -1};
auto [is_valid, new_i, len, number] = parse_number(s, i);
if (!is_valid) return {i, -1};
i = new_i;
result_extra_len += extra_len;
result_extra_len += len;
}
if (s[i] != '}') {
auto [new_i, extra_len] = parse_type(s, i);
if (extra_len < 0)
return {i, -1};
auto [is_valid, new_i, len, type] = parse_type(s, i);
if (is_valid) return {i, -1};
i = new_i;
result_extra_len += extra_len;
// result_extra_len += len;
}
return {i, result_extra_len};
@ -162,8 +190,7 @@ constexpr std::pair<unsigned, int> parse_braces(ConstString<N> s, unsigned i) {
++i;
auto [new_i, extra_len] = parse_fmt_string(s, i);
if (extra_len < 0)
return {i, -1};
if (extra_len < 0) return {i, -1};
i = new_i;
result_extra_len += extra_len;
@ -185,8 +212,7 @@ constexpr int get_output_len(ConstString<N> s) {
++i;
auto [new_i, extra_len] = parse_braces(s, i);
if (extra_len < 0)
return -1;
if (extra_len < 0) return -1;
i = new_i;
result_extra_len += extra_len;
@ -202,4 +228,15 @@ constexpr int get_output_len(ConstString<N> s) {
} // namespace detail
template <detail::ConstString s, typename... args_t>
const std::array<char, detail::get_output_len(s)> format(args_t...) {
constexpr int len = get_output_len(s);
static_assert(len > 0, "Syntax error in log string");
std::cout << "Computed Length: " << len << std::endl;
return {0};
}
#endif // LOGGER_PARSING_H

8
inc/utility.h
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@ -5,6 +5,14 @@
namespace detail {
constexpr std::size_t const_pow(std::size_t base, int exponent) {
if (exponent == 0)
return 1;
else
return base * const_pow(base, exponent -1);
}
template <std::size_t N>
class ConstString {
public:

2
src/main.cpp
View File

@ -16,7 +16,7 @@ int main() {
Uart uart;
Logger logger(uart);
logger.log<"Test format string: {:08.4f} {}">(1, 2, 3);
logger.log<"Test:{:88}">(1, 2, 3);
return 0;
}