Redirects the <string.h> names onto MMgr's bounded implementations. More...

#include "mmgr.h"
#include "cellularum_laboro/cellularum_laboro.h"
#include "memoria_operor/memoria_operor.h"

Macros
#define	memcpy(dest, source, bytes)
	Replaces memcpy with mmgr_shim_cpy.
#define	memmove(dest, source, bytes)
	Replaces memmove with mmgr_shim_move.
#define	memset(dest, value, bytes)
	Replaces memset with mmgr_shim_set.
#define	memcmp(left, right, bytes)
	Replaces memcmp with mmgr_shim_cmp.
#define	memchr(region, value, bytes)
	Replaces memchr with mmgr_shim_chr.
#define	strlen(text)
	Replaces strlen with a scan bounded at MMGR_STR_MAX.
#define	strnlen(text, limit)
	Replaces strnlen with a scan bounded at limit.
#define	strstr(haystack, needle)
	Replaces strstr with a case-sensitive search bounded at MMGR_STR_MAX.
#define	strcasestr(haystack, needle)
	Replaces strcasestr with a case-folded search bounded at MMGR_STR_MAX.
#define	strcmp(left, right)
	Replaces strcmp with an equality test bounded at MMGR_STR_MAX.
#define	strcasecmp(left, right)
	Replaces strcasecmp with a case-folded equality test bounded at MMGR_STR_MAX.
#define	strncmp(left, right, limit)
	Replaces strncmp with an equality test over at most limit bytes.
#define	strncasecmp(left, right, limit)
	Replaces strncasecmp with a case-folded equality test over at most limit bytes.
#define	strlcpy(dest, source, limit)
	Replaces strlcpy with a bounded copy that always terminates unless limit is 0.
#define	strchr(text, value)
	Replaces strchr with a search bounded at MMGR_STR_MAX.

Functions
static void *	mmgr_shim_cpy (void dest, const void source, size_t bytes)
	Copies bytes from source to dest and returns dest.
static void *	mmgr_shim_move (void dest, const void source, size_t bytes)
	Copies bytes from source to dest, tolerating overlap, and returns dest.
static void *	mmgr_shim_set (void *dest, embed_iword value, size_t bytes)
	Fills bytes of dest with the low byte of value and returns dest.
static embed_iword	mmgr_shim_cmp (const void left, const void right, size_t bytes)
	Compares bytes of left against right.
static void *	mmgr_shim_chr (const void *region, embed_iword value, size_t bytes)
	Finds the first byte in region equal to the low byte of value.

Detailed Description

Redirects the <string.h> names onto MMgr's bounded implementations.

Author: dstroy0 (Douglas Quigg) dquig.nosp@m.g123.nosp@m.@gmai.nosp@m.l.co.nosp@m.m

Date: 2026-08-30

Note: For code already written against <string.h> that has to run where there is no libc, or where an unbounded read is not acceptable. The call sites do not change. What the names mean does.; Defines the usual <string.h> include guards. A later #include <string.h> contributes nothing and the real declarations never arrive to conflict with these.; Not reached from mmgr.h. Including this changes what the <string.h> names mean, which is a decision a consumer makes for itself.

Warning: strcmp, strcasecmp, strncmp and strncasecmp report equality only and never order. Code that sorts with them is wrong here and compiles anyway.; Including this header changes the meaning of those names for the whole translation unit, including in headers it includes afterwards.; The six names bounded by MMGR_STR_MAX need the build to define it. Nothing here supplies a default, because the caller is what states how much storage there is.

Definition in file mmgr_string_shim.h.

Macro Definition Documentation

◆ memcpy

#define memcpy	(	dest,
		source,
		bytes )

Replaces memcpy with mmgr_shim_cpy.

Note: Every argument is parenthesized. Any expression may be passed.

Definition at line 152 of file mmgr_string_shim.h.

◆ memmove

#define memmove	(	dest,
		source,
		bytes )

Replaces memmove with mmgr_shim_move.

Note: Every argument is parenthesized, as in the memcpy shim.

Definition at line 159 of file mmgr_string_shim.h.

◆ memset

#define memset	(	dest,
		value,
		bytes )

Replaces memset with mmgr_shim_set.

Note: value reaches mmgr_shim_set as embed_iword and is narrowed there, the signature the real memset has and the reason the shim takes a word and not a byte.

Definition at line 167 of file mmgr_string_shim.h.

◆ memcmp

#define memcmp	(	left,
		right,
		bytes )

Replaces memcmp with mmgr_shim_cmp.

Note: Keeps the ordering the standard requires. The sign follows the first differing byte pair.

Definition at line 174 of file mmgr_string_shim.h.

◆ memchr

#define memchr	(	region,
		value,
		bytes )

Replaces memchr with mmgr_shim_chr.

Note: The only one of the five mem shims that is bounded by its own argument and not by a terminator, and so it needs no MMGR_STR_MAX and cannot stop short of what it was asked for.

Definition at line 182 of file mmgr_string_shim.h.

◆ strlen

#define strlen ( text )

Replaces strlen with a scan bounded at MMGR_STR_MAX.

Returns: Bytes before the terminator, at most MMGR_STR_MAX.

Warning: Returns MMGR_STR_MAX when no terminator appears within it, instead of scanning further.; text must be readable until its terminator, or for MMGR_STR_MAX bytes when it has none, with the tail word read whole as mmgr_cellul_len describes.

Definition at line 192 of file mmgr_string_shim.h.

◆ strnlen

#define strnlen	(		text,
			limit )

Replaces strnlen with a scan bounded at limit.

Returns: Bytes before the terminator, at most limit.

Note: Returns limit when no terminator appears within it, as strnlen does.

Warning: text must be readable until its terminator, or for limit bytes when it has none, with the tail word read whole as mmgr_cellul_len describes.

Definition at line 202 of file mmgr_string_shim.h.

◆ strstr

#define strstr	(		haystack,
			needle )

Replaces strstr with a case-sensitive search bounded at MMGR_STR_MAX.

Returns: Address inside haystack where needle begins, or NULL when it does not occur [BORROWS].

Note: The cast through size_t drops the const the backend returns, matching the strstr signature.

Warning: Both operands must be terminated within MMGR_STR_MAX. Without a terminator the search reads that many bytes from them.

Definition at line 212 of file mmgr_string_shim.h.

◆ strcasestr

#define strcasestr	(		haystack,
			needle )

Replaces strcasestr with a case-folded search bounded at MMGR_STR_MAX.

Returns: Address inside haystack where needle begins, or NULL when it does not occur [BORROWS].

Note: Differs from the strstr shim only in passing ci as EMBED_TRUE.

Warning: Both operands must be terminated within MMGR_STR_MAX. Without a terminator the search reads that many bytes from them.

Definition at line 224 of file mmgr_string_shim.h.

◆ strcmp

#define strcmp	(		left,
			right )

Replaces strcmp with an equality test bounded at MMGR_STR_MAX.

Returns: 0 when left and right hold the same string, 1 when they differ.

Note: Both == 0 and ! therefore test equality, as they do with the real strcmp.

Warning: Never negative and never above 1: it cannot be used to order strings.; Both operands must be terminated within MMGR_STR_MAX. Without a terminator the compare reads that many bytes from them.

Definition at line 237 of file mmgr_string_shim.h.

◆ strcasecmp

#define strcasecmp	(		left,
			right )

Replaces strcasecmp with a case-folded equality test bounded at MMGR_STR_MAX.

Returns: 0 when left and right hold the same string ignoring case, 1 when they differ.

Warning: Never negative and never above 1: it cannot be used to order strings.; Both operands must be terminated within MMGR_STR_MAX. Without a terminator the compare reads that many bytes from them.

Definition at line 248 of file mmgr_string_shim.h.

◆ strncmp

#define strncmp	(	left,
		right,
		limit )

Replaces strncmp with an equality test over at most limit bytes.

Returns: 0 when left and right agree through limit bytes, 1 when they differ before it.

Warning: Never negative and never above 1: it cannot be used to order strings.; A terminator does not end the comparison. All limit bytes must be readable in both operands, with the tail word read whole as mmgr_cellul_diff describes.; limit appears twice in the expansion. An argument with a side effect is evaluated twice.

Definition at line 260 of file mmgr_string_shim.h.

◆ strncasecmp

#define strncasecmp	(	left,
		right,
		limit )

Replaces strncasecmp with a case-folded equality test over at most limit bytes.

Returns: 0 when left and right agree through limit bytes ignoring case, 1 when they differ before it.

Warning: Never negative and never above 1: it cannot be used to order strings.; A terminator does not end the comparison. All limit bytes must be readable in both operands, with the tail word read whole as mmgr_cellul_diff describes.; limit appears twice in the expansion. An argument with a side effect is evaluated twice.

Definition at line 273 of file mmgr_string_shim.h.

◆ strlcpy

#define strlcpy	(	dest,
		source,
		limit )

Replaces strlcpy with a bounded copy that always terminates unless limit is 0.

Returns: Bytes copied and not counting the terminator.

Warning: Not the source length the real strlcpy returns. A caller cannot detect truncation by comparing the result against limit.; dest must be writable for limit bytes and source readable for limit minus one.

Definition at line 285 of file mmgr_string_shim.h.

◆ strchr

#define strchr	(		text,
			value )

Replaces strchr with a search bounded at MMGR_STR_MAX.

Returns: Address inside text where the byte occurs, or NULL when it does not [BORROWS].

Note: A value of 0 returns the address of the terminator, as strchr does.; The cast through size_t drops the const the backend returns, matching the strchr signature, and value is narrowed to uint8_t, the byte the search compares against.

Warning: text must be terminated within MMGR_STR_MAX. Without a terminator the search reads that many bytes from it.

Definition at line 298 of file mmgr_string_shim.h.

Function Documentation

◆ mmgr_shim_cpy()

void * mmgr_shim_cpy	(	void *	dest,
		const void *	source,
		size_t	bytes )

inlinestatic

Copies bytes from source to dest and returns dest.

Parameters

[out]	dest	Destination to write [BORROWS].
[in]	source	Bytes to read [BORROWS].
[in]	bytes	Number of bytes to copy.

Returns: dest [BORROWS].

Warning: The two regions must not overlap. Use mmgr_shim_move when they might.; dest must be writable for bytes and source readable for the same.

Definition at line 69 of file mmgr_string_shim.h.

References MemoriaCfg::dst, and mmgr_shim_cpy().

Referenced by mmgr_shim_cpy().

◆ mmgr_shim_move()

void * mmgr_shim_move	(	void *	dest,
		const void *	source,
		size_t	bytes )

inlinestatic

Copies bytes from source to dest, tolerating overlap, and returns dest.

Parameters

[out]	dest	Destination to write [BORROWS].
[in]	source	Bytes to read [BORROWS].
[in]	bytes	Number of bytes to copy.

Returns: dest [BORROWS].

Note: Compares the two addresses and walks upwards or downwards so overlapping bytes are read before they are written.

Warning: dest must be writable for bytes and source readable for the same.

Definition at line 86 of file mmgr_string_shim.h.

References MemoriaCfg::dst, and mmgr_shim_move().

Referenced by mmgr_shim_move().

◆ mmgr_shim_set()

void * mmgr_shim_set	(	void *	dest,
		embed_iword	value,
		size_t	bytes )

inlinestatic

Fills bytes of dest with the low byte of value and returns dest.

Parameters

[out]	dest	Destination to write [BORROWS].
[in]	value	Fill value, of which only the low eight bits are used.
[in]	bytes	Number of bytes to write.

Returns: dest [BORROWS].

Note: Explicit cast narrows value to uint8_t, matching the byte the fill writes.

Warning: dest must be writable for bytes.

Definition at line 111 of file mmgr_string_shim.h.

References MemoriaCfg::dst, and mmgr_shim_set().

Referenced by mmgr_shim_set().

◆ mmgr_shim_cmp()

embed_iword mmgr_shim_cmp	(	const void *	left,
		const void *	right,
		size_t	bytes )

inlinestatic

Compares bytes of left against right.

Parameters

[in]	left	First region [BORROWS].
[in]	right	Second region [BORROWS].
[in]	bytes	Number of bytes to compare.

Returns: Difference of the first unequal byte pair, or 0 when all bytes match.

Note: Unlike the strcmp shims, this one does order: the sign follows the differing bytes.

Warning: Both left and right must be readable for bytes.

Definition at line 127 of file mmgr_string_shim.h.

References mmgr_shim_cmp(), and MemoriaCfg::src.

Referenced by mmgr_shim_cmp().

◆ mmgr_shim_chr()

void * mmgr_shim_chr	(	const void *	region,
		embed_iword	value,
		size_t	bytes )

inlinestatic

Finds the first byte in region equal to the low byte of value.

Parameters

[in]	region	Bytes to search [BORROWS].
[in]	value	Byte sought, of which only the low eight bits are used.
[in]	bytes	Number of bytes to search.

Returns: Address of the match, or NULL when the byte does not occur [BORROWS].

Note: The cast through size_t drops the const the backend returns, matching the memchr signature.

Warning: region must be readable for bytes.

Definition at line 142 of file mmgr_string_shim.h.

References mmgr_shim_chr(), and MemoriaCfg::src.

Referenced by mmgr_shim_chr().

	MMgr v1.0.0 Zero-heap memory manager in C11. One borrowed buffer, carved by asserted offset.

Macros

Functions

Detailed Description

Macro Definition Documentation

◆ memcpy

◆ memmove

◆ memset

◆ memcmp

◆ memchr

◆ strlen

◆ strnlen

◆ strstr

◆ strcasestr

◆ strcmp

◆ strcasecmp

◆ strncmp

◆ strncasecmp

◆ strlcpy

◆ strchr

Function Documentation

◆ mmgr_shim_cpy()

◆ mmgr_shim_move()

◆ mmgr_shim_set()

◆ mmgr_shim_cmp()

◆ mmgr_shim_chr()