epagris/embfmt
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

programmable field width (e.g. %*c)

Browse Source
This commit is contained in:
Wiesner András 2023-02-14 19:12:49 +01:00
parent 9048955245
commit c1512cde98
1 changed files with 399 additions and 373 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

58
embformat.c
View File

@ -28,6 +28,7 @@ typedef enum {
} FmtType; } FmtType;
struct _FmtWord; struct _FmtWord;
typedef int (*printfn)(va_list *va, struct _FmtWord *fmt, char *outbuf, size_t free_space); typedef int (*printfn)(va_list *va, struct _FmtWord *fmt, char *outbuf, size_t free_space);
// pair of type and designator character // pair of type and designator character
@ -260,7 +261,7 @@ static int pfn_double(va_list *va, FmtWord *fmt, char *outbuf, size_t free_space
} }
// formatting of the integer part // formatting of the integer part
FmtWord int_fmt = { .flags = fmt->flags, .type = UNSIGNED_INTEGER, .width = fmt->width }; FmtWord int_fmt = {.flags = fmt->flags, .type = UNSIGNED_INTEGER, .width = fmt->width};
// separate into integer and fractional part // separate into integer and fractional part
uint64_t int_part = (uint64_t) d; // integer part uint64_t int_part = (uint64_t) d; // integer part
@ -281,7 +282,7 @@ static int pfn_double(va_list *va, FmtWord *fmt, char *outbuf, size_t free_space
*outbuf = '\0'; *outbuf = '\0';
// prepare format for printing fractional part // prepare format for printing fractional part
FmtWord frac_fmt = { .flags = FLAG_NO, .width = -1, .type = UNSIGNED_INTEGER }; FmtWord frac_fmt = {.flags = FLAG_NO, .width = -1, .type = UNSIGNED_INTEGER};
// get "leading zeros" in fractional part // get "leading zeros" in fractional part
double d_frac = d - (double) int_part; double d_frac = d - (double) int_part;
@ -320,7 +321,7 @@ static int pfn_double(va_list *va, FmtWord *fmt, char *outbuf, size_t free_space
sum_copy_len++; sum_copy_len++;
// print value of exponent // print value of exponent
FmtWord exponent_fmt = { .flags = FLAG_PREPEND_PLUS_SIGN | FLAG_LEADING_ZEROS, .width = 2, .type = UNSIGNED_INTEGER }; FmtWord exponent_fmt = {.flags = FLAG_PREPEND_PLUS_SIGN | FLAG_LEADING_ZEROS, .width = 2, .type = UNSIGNED_INTEGER};
unsigned int exponent_abs = exponent > 0 ? exponent : -exponent; unsigned int exponent_abs = exponent > 0 ? exponent : -exponent;
@ -336,11 +337,13 @@ static int pfn_double(va_list *va, FmtWord *fmt, char *outbuf, size_t free_space
// print character // print character
static int pfn_char(va_list *va, FmtWord *fmt, char *outbuf, size_t free_space) { static int pfn_char(va_list *va, FmtWord *fmt, char *outbuf, size_t free_space) {
int c = va_arg((*va), int); int c = va_arg((*va), int);
if (free_space >= 1) { unsigned rep = (fmt->width == 0) ? 1 : fmt->width; // determine repetition count
outbuf[0] = (char) c; rep = MIN(free_space, rep);
outbuf[1] = '\0'; for (unsigned i = 0; i < rep; i++) {
outbuf[i] = (char)c;
} }
return 1; outbuf[rep] = '\0';
return rep;
} }
// print string // print string
@ -350,16 +353,25 @@ static int pfn_string(va_list *va, FmtWord *fmt, char *outbuf, size_t free_space
} }
// format swting assignment table // format swting assignment table
static FmtTypeDesignatorPair sTypeDesAssignment[] = { { '%', LITERAL_PERCENT, pfn_literal_percent }, { 'd', SIGNED_INTEGER, pfn_integer }, { 'i', SIGNED_INTEGER, pfn_integer }, { 'u', static FmtTypeDesignatorPair sTypeDesAssignment[] = {{'%', LITERAL_PERCENT, pfn_literal_percent},
UNSIGNED_INTEGER, pfn_integer }, { 'f', DOUBLE, pfn_double }, { 'e', DOUBLE_EXPONENTIAL, pfn_double }, { 'x', UNSIGNED_HEXADECIMAL_INT, pfn_integer }, { 'X', {'d', SIGNED_INTEGER, pfn_integer},
UNSIGNED_HEXADECIMAL_INT_UPPERCASE, pfn_integer }, { 'p', UNSIGNED_HEXADECIMAL_INT, pfn_integer }, { 's', STRING, pfn_string }, { 'c', CHARACTER, pfn_char }, { '\0', UNKNOWN } // termination {'i', SIGNED_INTEGER, pfn_integer},
{'u', UNSIGNED_INTEGER, pfn_integer},
{'f', DOUBLE, pfn_double},
{'e', DOUBLE_EXPONENTIAL, pfn_double},
{'x', UNSIGNED_HEXADECIMAL_INT, pfn_integer},
{'X', UNSIGNED_HEXADECIMAL_INT_UPPERCASE, pfn_integer},
{'p', UNSIGNED_HEXADECIMAL_INT, pfn_integer},
{'s', STRING, pfn_string},
{'c', CHARACTER, pfn_char},
{'\0', UNKNOWN} // termination
}; };
// ------------------------------------------------------------ // ------------------------------------------------------------
// try to fetch number from the start of the string // try to fetch number from the start of the string
// return: number found OR -1 on failure // return: number found OR -1 on failure
static char* fetch_number(char *str, int *num) { static char *fetch_number(char *str, int *num) {
char *start = str; char *start = str;
char *end = start; char *end = start;
*num = 0; *num = 0;
@ -394,7 +406,7 @@ static int get_number_of_arguments_by_format_string(char *format_str) {
} }
// seek for format delimiter ('%') // seek for format delimiter ('%')
static char* seek_delimiter(char *str) { static char *seek_delimiter(char *str) {
// iterate over characters until either '%' is found or end of string is reached // iterate over characters until either '%' is found or end of string is reached
while (*(str) != '\0' && *(str) != FORMAT_DELIMITER) { while (*(str) != '\0' && *(str) != FORMAT_DELIMITER) {
str++; str++;
@ -413,7 +425,7 @@ static char* seek_delimiter(char *str) {
// begin: pointer to pointer to the begin of the format word // begin: pointer to pointer to the begin of the format word
// length: length of the format word (number of bytes to be copied after) // length: length of the format word (number of bytes to be copied after)
// return: pointer to unprocessed input string // return: pointer to unprocessed input string
static char* locate_format_word(char *str, char **begin, size_t *length) { static char *locate_format_word(char *str, char **begin, size_t *length) {
char *delim_pos = seek_delimiter(str); // seek for format specifier begin char *delim_pos = seek_delimiter(str); // seek for format specifier begin
if (delim_pos == NULL) { // if not found... if (delim_pos == NULL) { // if not found...
*length = 0; // set to zero if not found *length = 0; // set to zero if not found
@ -447,7 +459,7 @@ static char* locate_format_word(char *str, char **begin, size_t *length) {
// preceding_text: text before format word // preceding_text: text before format word
// maxlen: maximum STRING LENGTH of the output // maxlen: maximum STRING LENGTH of the output
// return: pointer to unprocessed text OR NULL on failure // return: pointer to unprocessed text OR NULL on failure
static char* fetch_format_word(char *str, char *word, char **word_begin, size_t maxlen) { static char *fetch_format_word(char *str, char *word, char **word_begin, size_t maxlen) {
// locate word // locate word
size_t len; size_t len;
char *unproc_text = locate_format_word(str, word_begin, &len); char *unproc_text = locate_format_word(str, word_begin, &len);
@ -459,7 +471,7 @@ static char* fetch_format_word(char *str, char *word, char **word_begin, size_t
} }
// fetch type from designator character // fetch type from designator character
static FmtTypeDesignatorPair* get_type_by_designator(char designator) { static FmtTypeDesignatorPair *get_type_by_designator(char designator) {
FmtTypeDesignatorPair *iter = sTypeDesAssignment; FmtTypeDesignatorPair *iter = sTypeDesAssignment;
while (iter->designator != '\0' && iter->designator != designator) { while (iter->designator != '\0' && iter->designator != designator) {
iter++; iter++;
@ -468,6 +480,7 @@ static FmtTypeDesignatorPair* get_type_by_designator(char designator) {
} }
#define DEFAULT_PRINT_PRECISION (6) #define DEFAULT_PRINT_PRECISION (6)
#define LENGTH_IS_PARAMETER (-2) // -1 is used for something else
static char sFlags[] = " 0+"; static char sFlags[] = " 0+";
@ -507,7 +520,12 @@ static int process_format_word(char *str, FmtWord *word, int *rewind) {
} }
// 2.: look for width // 2.: look for width
if (*str == '*') { // parametered width
str++;
word->width = LENGTH_IS_PARAMETER; // read length from the varargs
} else {
str = fetch_number(str, &(word->width)); str = fetch_number(str, &(word->width));
}
// 3.: look for precision // 3.: look for precision
word->precision = DEFAULT_PRINT_PRECISION; // default double precision word->precision = DEFAULT_PRINT_PRECISION; // default double precision
@ -555,11 +573,19 @@ unsigned long int vembfmt(char *str, unsigned long int len, char *format, va_lis
sum_copy_len += copy_len; sum_copy_len += copy_len;
// print data // print data
FmtWord word; FmtWord word = { 0 };
int rewind; int rewind;
process_format_word(word_str, &word, &rewind); process_format_word(word_str, &word, &rewind);
if (word.type != UNKNOWN) { if (word.type != UNKNOWN) {
if (word.width == LENGTH_IS_PARAMETER) { // if length is passed in parameter...
word.width = va_arg(args, unsigned); // read length parameter
}
#ifdef COMPILE_FOR_LINUX
int copy_len = word.pTypeDes->fn(args, &word, str, free_space); // variable with the same name!
#else
int copy_len = word.pTypeDes->fn(&args, &word, str, free_space); // variable with the same name! int copy_len = word.pTypeDes->fn(&args, &word, str, free_space); // variable with the same name!
#endif
free_space -= copy_len; free_space -= copy_len;
str += copy_len; str += copy_len;
sum_copy_len += copy_len; sum_copy_len += copy_len;