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| author | Maarten Lankhorst <maarten.lankhorst@linux.intel.com> | 2021-07-27 12:48:17 +0200 | 
|---|---|---|
| committer | Maarten Lankhorst <maarten.lankhorst@linux.intel.com> | 2021-07-27 12:48:17 +0200 | 
| commit | ca31fef11dc83e672415d5925a134749761329bd (patch) | |
| tree | 8eb6a489e2d6dd117300f40ed8fc945a06bb6eee /lib/string_helpers.c | |
| parent | ba6cd766e0bf933611dc66fcb86f72ac80a446bc (diff) | |
| parent | 15d27b15de965043d6f8e23bc7f34386fcd1a772 (diff) | |
Backmerge remote-tracking branch 'drm/drm-next' into drm-misc-next
Required bump from v5.13-rc3 to v5.14-rc3, and to pick up sysfb compilation fixes.
Signed-off-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Diffstat (limited to 'lib/string_helpers.c')
| -rw-r--r-- | lib/string_helpers.c | 102 | 
1 files changed, 61 insertions, 41 deletions
diff --git a/lib/string_helpers.c b/lib/string_helpers.c index 7f2d5fbaf243..5a35c7e16e96 100644 --- a/lib/string_helpers.c +++ b/lib/string_helpers.c @@ -452,18 +452,20 @@ static bool escape_hex(unsigned char c, char **dst, char *end)   * The process of escaping byte buffer includes several parts. They are applied   * in the following sequence.   * - *	1. The character is matched to the printable class, if asked, and in - *	   case of match it passes through to the output. - *	2. The character is not matched to the one from @only string and thus + *	1. The character is not matched to the one from @only string and thus   *	   must go as-is to the output. - *	3. The character is checked if it falls into the class given by @flags. + *	2. The character is matched to the printable and ASCII classes, if asked, + *	   and in case of match it passes through to the output. + *	3. The character is matched to the printable or ASCII class, if asked, + *	   and in case of match it passes through to the output. + *	4. The character is checked if it falls into the class given by @flags.   *	   %ESCAPE_OCTAL and %ESCAPE_HEX are going last since they cover any   *	   character. Note that they actually can't go together, otherwise   *	   %ESCAPE_HEX will be ignored.   *   * Caller must provide valid source and destination pointers. Be aware that   * destination buffer will not be NULL-terminated, thus caller have to append - * it if needs.   The supported flags are:: + * it if needs. The supported flags are::   *   *	%ESCAPE_SPACE: (special white space, not space itself)   *		'\f' - form feed @@ -482,11 +484,27 @@ static bool escape_hex(unsigned char c, char **dst, char *end)   *	%ESCAPE_ANY:   *		all previous together   *	%ESCAPE_NP: - *		escape only non-printable characters (checked by isprint) + *		escape only non-printable characters, checked by isprint()   *	%ESCAPE_ANY_NP:   *		all previous together   *	%ESCAPE_HEX:   *		'\xHH' - byte with hexadecimal value HH (2 digits) + *	%ESCAPE_NA: + *		escape only non-ascii characters, checked by isascii() + *	%ESCAPE_NAP: + *		escape only non-printable or non-ascii characters + *	%ESCAPE_APPEND: + *		append characters from @only to be escaped by the given classes + * + * %ESCAPE_APPEND would help to pass additional characters to the escaped, when + * one of %ESCAPE_NP, %ESCAPE_NA, or %ESCAPE_NAP is provided. + * + * One notable caveat, the %ESCAPE_NAP, %ESCAPE_NP and %ESCAPE_NA have the + * higher priority than the rest of the flags (%ESCAPE_NAP is the highest). + * It doesn't make much sense to use either of them without %ESCAPE_OCTAL + * or %ESCAPE_HEX, because they cover most of the other character classes. + * %ESCAPE_NAP can utilize %ESCAPE_SPACE or %ESCAPE_SPECIAL in addition to + * the above.   *   * Return:   * The total size of the escaped output that would be generated for @@ -500,67 +518,69 @@ int string_escape_mem(const char *src, size_t isz, char *dst, size_t osz,  	char *p = dst;  	char *end = p + osz;  	bool is_dict = only && *only; +	bool is_append = flags & ESCAPE_APPEND;  	while (isz--) {  		unsigned char c = *src++; +		bool in_dict = is_dict && strchr(only, c);  		/*  		 * Apply rules in the following sequence: -		 *	- the character is printable, when @flags has -		 *	  %ESCAPE_NP bit set  		 *	- the @only string is supplied and does not contain a  		 *	  character under question +		 *	- the character is printable and ASCII, when @flags has +		 *	  %ESCAPE_NAP bit set +		 *	- the character is printable, when @flags has +		 *	  %ESCAPE_NP bit set +		 *	- the character is ASCII, when @flags has +		 *	  %ESCAPE_NA bit set  		 *	- the character doesn't fall into a class of symbols  		 *	  defined by given @flags  		 * In these cases we just pass through a character to the  		 * output buffer. +		 * +		 * When %ESCAPE_APPEND is passed, the characters from @only +		 * have been excluded from the %ESCAPE_NAP, %ESCAPE_NP, and +		 * %ESCAPE_NA cases.  		 */ -		if ((flags & ESCAPE_NP && isprint(c)) || -		    (is_dict && !strchr(only, c))) { -			/* do nothing */ -		} else { -			if (flags & ESCAPE_SPACE && escape_space(c, &p, end)) -				continue; +		if (!(is_append || in_dict) && is_dict && +					  escape_passthrough(c, &p, end)) +			continue; -			if (flags & ESCAPE_SPECIAL && escape_special(c, &p, end)) -				continue; +		if (!(is_append && in_dict) && isascii(c) && isprint(c) && +		    flags & ESCAPE_NAP && escape_passthrough(c, &p, end)) +			continue; -			if (flags & ESCAPE_NULL && escape_null(c, &p, end)) -				continue; +		if (!(is_append && in_dict) && isprint(c) && +		    flags & ESCAPE_NP && escape_passthrough(c, &p, end)) +			continue; -			/* ESCAPE_OCTAL and ESCAPE_HEX always go last */ -			if (flags & ESCAPE_OCTAL && escape_octal(c, &p, end)) -				continue; +		if (!(is_append && in_dict) && isascii(c) && +		    flags & ESCAPE_NA && escape_passthrough(c, &p, end)) +			continue; -			if (flags & ESCAPE_HEX && escape_hex(c, &p, end)) -				continue; -		} +		if (flags & ESCAPE_SPACE && escape_space(c, &p, end)) +			continue; -		escape_passthrough(c, &p, end); -	} +		if (flags & ESCAPE_SPECIAL && escape_special(c, &p, end)) +			continue; -	return p - dst; -} -EXPORT_SYMBOL(string_escape_mem); +		if (flags & ESCAPE_NULL && escape_null(c, &p, end)) +			continue; -int string_escape_mem_ascii(const char *src, size_t isz, char *dst, -					size_t osz) -{ -	char *p = dst; -	char *end = p + osz; +		/* ESCAPE_OCTAL and ESCAPE_HEX always go last */ +		if (flags & ESCAPE_OCTAL && escape_octal(c, &p, end)) +			continue; -	while (isz--) { -		unsigned char c = *src++; +		if (flags & ESCAPE_HEX && escape_hex(c, &p, end)) +			continue; -		if (!isprint(c) || !isascii(c) || c == '"' || c == '\\') -			escape_hex(c, &p, end); -		else -			escape_passthrough(c, &p, end); +		escape_passthrough(c, &p, end);  	}  	return p - dst;  } -EXPORT_SYMBOL(string_escape_mem_ascii); +EXPORT_SYMBOL(string_escape_mem);  /*   * Return an allocated string that has been escaped of special characters  | 
