kgoba-ft8_lib/ft8/text.c

254 wiersze
4.8 KiB
C

#include "text.h"
#include <string.h>
const char* trim_front(const char* str)
{
// Skip leading whitespace
while (*str == ' ')
{
str++;
}
return str;
}
void trim_back(char* str)
{
// Skip trailing whitespace by replacing it with '\0' characters
int idx = strlen(str) - 1;
while (idx >= 0 && str[idx] == ' ')
{
str[idx--] = '\0';
}
}
// 1) trims a string from the back by changing whitespaces to '\0'
// 2) trims a string from the front by skipping whitespaces
char* trim(char* str)
{
str = (char*)trim_front(str);
trim_back(str);
// return a pointer to the first non-whitespace character
return str;
}
char to_upper(char c)
{
return (c >= 'a' && c <= 'z') ? (c - 'a' + 'A') : c;
}
bool is_digit(char c)
{
return (c >= '0') && (c <= '9');
}
bool is_letter(char c)
{
return ((c >= 'A') && (c <= 'Z')) || ((c >= 'a') && (c <= 'z'));
}
bool is_space(char c)
{
return (c == ' ');
}
bool in_range(char c, char min, char max)
{
return (c >= min) && (c <= max);
}
bool starts_with(const char* string, const char* prefix)
{
return 0 == memcmp(string, prefix, strlen(prefix));
}
bool equals(const char* string1, const char* string2)
{
return 0 == strcmp(string1, string2);
}
int char_index(const char* string, char c)
{
for (int i = 0; *string; ++i, ++string)
{
if (c == *string)
{
return i;
}
}
return -1; // Not found
}
// Text message formatting:
// - replaces lowercase letters with uppercase
// - merges consecutive spaces into single space
void fmtmsg(char* msg_out, const char* msg_in)
{
char c;
char last_out = 0;
while ((c = *msg_in))
{
if (c != ' ' || last_out != ' ')
{
last_out = to_upper(c);
*msg_out = last_out;
++msg_out;
}
++msg_in;
}
*msg_out = 0; // Add zero termination
}
// Parse a 2 digit integer from string
int dd_to_int(const char* str, int length)
{
int result = 0;
bool negative;
int i;
if (str[0] == '-')
{
negative = true;
i = 1; // Consume the - sign
}
else
{
negative = false;
i = (str[0] == '+') ? 1 : 0; // Consume a + sign if found
}
while (i < length)
{
if (str[i] == 0)
break;
if (!is_digit(str[i]))
break;
result *= 10;
result += (str[i] - '0');
++i;
}
return negative ? -result : result;
}
// Convert a 2 digit integer to string
void int_to_dd(char* str, int value, int width, bool full_sign)
{
if (value < 0)
{
*str = '-';
++str;
value = -value;
}
else if (full_sign)
{
*str = '+';
++str;
}
int divisor = 1;
for (int i = 0; i < width - 1; ++i)
{
divisor *= 10;
}
while (divisor >= 1)
{
int digit = value / divisor;
*str = '0' + digit;
++str;
value -= digit * divisor;
divisor /= 10;
}
*str = 0; // Add zero terminator
}
// convert integer index to ASCII character according to one of 6 tables:
// table 0: " 0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZ+-./?"
// table 1: " 0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZ"
// table 2: "0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZ"
// table 3: "0123456789"
// table 4: " ABCDEFGHIJKLMNOPQRSTUVWXYZ"
// table 5: " 0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZ/"
char charn(int c, int table_idx)
{
if (table_idx != 2 && table_idx != 3)
{
if (c == 0)
return ' ';
c -= 1;
}
if (table_idx != 4)
{
if (c < 10)
return '0' + c;
c -= 10;
}
if (table_idx != 3)
{
if (c < 26)
return 'A' + c;
c -= 26;
}
if (table_idx == 0)
{
if (c < 5)
return "+-./?"[c];
}
else if (table_idx == 5)
{
if (c == 0)
return '/';
}
return '_'; // unknown character, should never get here
}
// Convert character to its index (charn in reverse) according to a table
int nchar(char c, int table_idx)
{
int n = 0;
if (table_idx != 2 && table_idx != 3)
{
if (c == ' ')
return n + 0;
n += 1;
}
if (table_idx != 4)
{
if (c >= '0' && c <= '9')
return n + (c - '0');
n += 10;
}
if (table_idx != 3)
{
if (c >= 'A' && c <= 'Z')
return n + (c - 'A');
n += 26;
}
if (table_idx == 0)
{
if (c == '+')
return n + 0;
if (c == '-')
return n + 1;
if (c == '.')
return n + 2;
if (c == '/')
return n + 3;
if (c == '?')
return n + 4;
}
else if (table_idx == 5)
{
if (c == '/')
return n + 0;
}
// Character not found
return -1;
}