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57 lines
1.5 KiB
Markdown
57 lines
1.5 KiB
Markdown
### Length prefixed string
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Length prefixed C strings, length is at the start of the allocated memory
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e.g :
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-----------------------------------------------
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| 0 | 0 | 0 | 4 | 'T' | 'E' | 'S' | 'T' | '\0'|
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-----------------------------------------------
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^
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return
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User can keep pointer to first character, so it's like C style strings with
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additional functionality.
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### Pros
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- User gets a null terminated `char*`, so it still works with c style string
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functions, e.g printf, strcmp.
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- This implementation is mostly about avoiding strlen() cost.
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Provides a few more functions to make easier create/append/trim/substring
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operations.
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### Cons
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- 4 bytes fixed overhead per string and max string size is ~4gb.
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- When you create/set/append a string, new memory is allocated. If you are
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modifying strings a lot, consider using buffer-like implementation for that if
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performance is critical for your use-case. I modify strings rarely but read
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a lot (copy/move etc.).
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```c
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#include "sc_str.h"
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#include <stdio.h>
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int main(int argc, char *argv[])
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{
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char* s1;
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s1 = sc_str_create("*-hello-*");
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printf("%s \n", s1); // prints *-hello-*
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sc_str_trim(&s1, "*-");
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printf("%s \n", s1); // prints hello
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sc_str_append_fmt(&s1, "%d", 2);
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printf("%s \n", s1); // prints hello2
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sc_str_replace(&s1, "2", " world!");
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printf("%s \n", s1); // prints hello world!
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sc_str_substring(&s1, 0, 5);
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printf("%s \n", s1); // prints hello
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sc_str_destroy(s1);
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return 0;
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}
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``` |