str.c File Reference

#include <unistd.h>
#include "str.h"

Include dependency graph for str.c:

Functions
char *	strdup_maybe_entry (const char *restrict s, const struct ExecPoint ep, const int exit_code)
int	num_chars (const char *sptr, int ch)
int	startswith (const char *sptr, const char *pattern)
int	endswith (const char *sptr, const char *pattern)
void	strchrdel (char *sptr, const char *chars)
char **	split (char *_sptr, const char *delim, size_t max)
char *	join (char **arr, const char *separator)
char *	join_ex (char *separator,...)
char *	substring_between (char *sptr, const char *delims)
void	strsort (char **arr, unsigned int sort_mode)
char *	strstr_array (char **arr, const char *str)
char **	strdeldup (char **arr)
char *	lstrip (char *sptr)
char *	strip (char *sptr)
int	isempty (char *sptr)
int	isquoted (char *sptr)
int	isrelational (char ch)
void	print_banner (const char *s, int len)
char *	normalize_space (char *s)
char **	strdup_array (char **array)
int	strcmp_array (const char **a, const char **b)
int	isdigit_s (const char *s)
char *	tolower_s (char *s)
char *	to_short_version (const char *s)
void	unindent (char *s)
char *	remove_extras (char *s)

Function Documentation

endswith()

int endswith	(	const char *	sptr,
		const char *	pattern )

Scan for pattern string at the end of sptr

Parameters

sptr	string to scan
pattern	string to search for

Returns

1 = found, 0 = not found / error

isdigit_s()

int isdigit_s

(

const char *

s

)

Determine whether a string is comprised of digits

Parameters

s

Returns

0=no, 1=yes

isempty()

int isempty

(

char *

sptr

)

Check if a given string is "visibly" empty

char visibly[100];
 
strcpy(visibly, "\t     \t\n");
if (isempty(visibly)) {
    printf("string is 'empty'\n");
} else {
    printf("string is not 'empty'\n");
}

Parameters

sptr	pointer to string

Returns

0=not empty, 1=empty

isquoted()

int isquoted

(

char *

sptr

)

Determine if a string is encapsulated by quotes

Parameters

sptr	pointer to string

Returns

0=not quoted, 1=quoted

isrelational()

int isrelational

(

char

ch

)

Determine whether the input character is a relational operator Note: ~ is non-standard

Parameters

ch

Returns

0=no, 1=yes

join()

char * join	(	char **	arr,
		const char *	separator )

Create new a string from an array of strings

char *array[] = {
    "this",
    "is",
    "a",
    "test",
    NULL,
}
 
char *test = join(array, " ");    // "this is a test"
char *test2 = join(array, "_");   // "this_is_a_test"
char *test3 = join(array, ", ");  // "this, is, a, test"
 
free(test);
free(test2);
free(test3);

Parameters

arr
separator	characters to insert between elements in string

Returns

new joined string

join_ex()

char * join_ex	(	char *	separator,
			... )

Join two or more strings by a separator string

Parameters

separator
...

Returns

string

lstrip()

char * lstrip

(

char *

sptr

)

Remove leading whitespace from a string

char input[100];
 
strcpy(input, "          I had leading spaces");
lstrip(input);
// input is now "I had leading spaces"

Parameters

sptr	pointer to string

Returns

pointer to first non-whitespace character in string

normalize_space()

char * normalize_space

(

char *

s

)

Collapse whitespace in s. The string is modified in place.

Parameters

s

Returns

pointer to s

num_chars()

int num_chars	(	const char *	sptr,
		int	ch )

Determine how many times the character ch appears in sptr string

Parameters

sptr	string to scan
ch	character to find

Returns

count of characters found

print_banner()

void print_banner	(	const char *	s,
		int	len )

Print characters in s, len times

Parameters

s
len

split()

char ** split	(	char *	sptr,
		const char *	delim,
		size_t	max )

Split a string by every delimiter in delim string.

Callee should free memory using GENERIC_ARRAY_FREE()

Parameters

sptr	string to split
delim	characters to split on

Returns

success=parts of string, failure=NULL

Here is the call graph for this function:

startswith()

int startswith	(	const char *	sptr,
		const char *	pattern )

Scan for pattern string at the beginning of sptr

Parameters

sptr	string to scan
pattern	string to search for

Returns

1 = found, 0 = not found / error

strchrdel()

void strchrdel	(	char *	sptr,
		const char *	chars )

Deletes any characters matching chars from sptr string

Parameters

sptr	string to be modified in-place
chars	a string containing characters (e.g. " \n" would delete whitespace and line feeds)

Here is the call graph for this function:

strcmp_array()

int strcmp_array	(	const char **	a,
		const char **	b )

Compare an array of strings

const char *a[] = {
    "I",
    "like",
    "computers."
};
const char *b[] = {
    "I",
    "like",
    "cars."
};
if (!strcmp_array(a, b)) {
    printf("a and b are not equal\n");
} else {
    printf("a and b are equal\n");
}

Parameters

a	pointer to array
b	poitner to array

Returns

0 on identical, non-zero for different

strdeldup()

char ** strdeldup

(

char **

arr

)

Remove duplicate strings from an array of strings

Parameters

arr

Returns

success=array of unique strings, failure=NULL

Here is the call graph for this function:

strdup_array()

char ** strdup_array

(

char **

array

)

Duplicate an array of strings

char **array_orig = calloc(10, sizeof(*orig));
orig[0] = strdup("one");
orig[1] = strdup("two");
orig[2] = strdup("three");
// ...
char **array_orig_copy = strdup_array(orig);
 
for (size_t i = 0; array_orig_copy[i] != NULL; i++) {
    printf("array_orig[%zu] = '%s'\narray_orig_copy[%zu] = '%s'\n\n",
           i, array_orig[i],
           i, array_orig_copy[i]);
    free(array_orig_copy[i]);
    free(array_orig[i]);
}
free(array_orig_copy);
free(array_orig);

Parameters

array

Returns

strip()

char * strip

(

char *

sptr

)

Strips trailing whitespace from a given string

char input[100];
 
strcpy(input, "I had trailing spaces          ");
strip(input);
// input is now "I had trailing spaces"

Parameters

sptr	input string

Returns

truncated string

strsort()

void strsort	(	char **	arr,
		unsigned int	sort_mode )

Sort an array of strings

Parameters

arr	a NULL terminated array of strings
sort_mode	STASIS_SORT_LEN_DESCENDING STASIS_SORT_LEN_ASCENDING STASIS_SORT_ALPHA STASIS_SORT_NUMERIC

strstr_array()

char * strstr_array	(	char **	arr,
		const char *	str )

Search for string in an array of strings

Parameters

arr	array of strings
str	string to search for

Returns

yes=pointer to string, no=NULL, failure=NULL

substring_between()

char * substring_between	(	char *	sptr,
		const char *	delims )

Extract the string encapsulated by characters listed in delims

char *str = "this is [some data] in a string";
char *data = substring_between(string, "[]");
// data = "some data";

Parameters

sptr	string to parse
delims	two characters surrounding a string

Returns

success=text between delimiters, failure=NULL

to_short_version()

char * to_short_version

(

const char *

s

)

Reduce a version string to the major[minor] format used by Python

#include <stdio.h>
#include "str.h"
 
int main(int argc, char *argv[]) {
    char python_version[] = "3.13.3"
    char *python_short_version = to_short_version(python_version);  // "313"
    if (!python_short_version) {
        perror("unable to allocate memory for shortened python version");
        return 1;
    }
    free(python_short_version);
    return 0;
}

Parameters

s	python version string

Returns

the shortened version string

NULL on error

Here is the call graph for this function:

tolower_s()

char * tolower_s

(

char *

s

)

Convert input string to lowercase

char *str = strdup("HELLO WORLD!");
tolower_s(str);
// str is "hello world!"

Parameters

s	input string

Returns

pointer to input string