FM / tapset

/usr/share/systemtap/tapset

Name	Size	Mode	Actions
arm/	-	0755	rm
arm64/	-	0755	rm
bpf/	-	0755	rm
dyninst/	-	0755	rm
i386/	-	0755	rm
ia64/	-	0755	rm
linux/	-	0755	rm
mips/	-	0755	rm
powerpc/	-	0755	rm
riscv/	-	0755	rm
s390/	-	0755	rm
x86_64/	-	0755	rm
ansi.stp	4178	0644	edit dl rm
argv.stp	2721	0644	edit dl rm
choose_defined.stpm	208	0644	edit dl rm
container_of.stpm	235	0644	edit dl rm
context.stp	6103	0644	edit dl rm
errno.stp	9118	0644	edit dl rm
floatingpoint.stp	6936	0644	edit dl rm
indent-default.stp	59	0644	edit dl rm
indent.stp	4590	0644	edit dl rm
init.stp	269	0644	edit dl rm
input.stp	263	0644	edit dl rm
java.stp	1346	0644	edit dl rm
libperl5.26.3-64.stp	1339	0644	edit dl rm
libpython2.7-64.stp	522	0644	edit dl rm
livepatch.stp	3006	0644	edit dl rm
logging.stp	4132	0644	edit dl rm
macros.stpm	562	0644	edit dl rm
null.stp	17	0644	edit dl rm
offsetof.stpm	183	0644	edit dl rm
oneshot.stp	38	0644	edit dl rm
pn.stp	1588	0644	edit dl rm
print_stats.stpm	1719	0644	edit dl rm
private30.stpm	80	0644	edit dl rm
prometheus.stp	129	0644	edit dl rm
prometheus.stpm	8380	0644	edit dl rm
python.stp	474	0644	edit dl rm
python2.stp	29435	0644	edit dl rm
python3.stp	36655	0644	edit dl rm
queue_stats.stp	9487	0644	edit dl rm
random.stp	432	0644	edit dl rm
README	371	0644	edit dl rm
regex.stp	4107	0644	edit dl rm
registers.stp	11081	0644	edit dl rm
sizeof.stpm	212	0644	edit dl rm
speculative.stp	1746	0644	edit dl rm
sreg_arch.stpm	263	0644	edit dl rm
stap_staticmarkers.stp	9670	0644	edit dl rm
stopwatch.stp	3063	0644	edit dl rm
string.stp	7514	0644	edit dl rm
switchfile.stp	612	0644	edit dl rm
system.stp	593	0644	edit dl rm
this.stp	160	0644	edit dl rm
timers.stp	924	0644	edit dl rm
tls.stp	8099	0644	edit dl rm
tokenize.stp	2124	0644	edit dl rm
try_assign.stpm	768	0644	edit dl rm
type_defined.stpm	374	0644	edit dl rm
tzinfo.stp	930	0644	edit dl rm
uconversions-guru.stp	6078	0644	edit dl rm
uconversions.stp	36640	0644	edit dl rm

Edit: /usr/share/systemtap/tapset/string.stp (7514B)

// Standard string functions tapset.
// Copyright (C) 2009-2019 Red Hat, Inc.
//
// This file is part of systemtap, and is free software.  You can
// redistribute it and/or modify it under the terms of the GNU General
// Public License (GPL); either version 2, or (at your option) any
// later version.

/**
 * sfunction strlen - Returns the length of a string
 *
 * @s: the string
 *
 * Description: This function returns the length of the string, which
 * can be zero up to MAXSTRINGLEN.
 */
function strlen:long(s:string)
%{ /* pure */ /* unprivileged */ /* unmodified-fnargs */
	STAP_RETURN(strlen(STAP_ARG_s));
%}

/**
 * sfunction substr - Returns a substring
 *
 * @str: the string to take a substring from
 * @start: starting position of the extracted string (first character is 0)
 * @length: length of string to return
 *
 * Description: Returns the substring of the given string at the given
 * start position with the given length (or smaller if the length of the
 * original string is less than start + length, or length is bigger than
 * MAXSTRINGLEN).
 */
function substr:string(str:string,start:long, length:long)
%{ /* pure */ /* unprivileged */ /* unmodified-fnargs */
	int64_t length = clamp_t(int64_t, STAP_ARG_length + 1, 0, MAXSTRINGLEN);
	if (STAP_ARG_start >= 0 && STAP_ARG_start < strlen(STAP_ARG_str))
		strlcpy(STAP_RETVALUE, STAP_ARG_str + STAP_ARG_start, length);
%}

/**
 * sfunction stringat - Returns the char at a given position in the string
 *
 * @str: the string to fetch the character from
 * @pos: the position to get the character from  (first character is 0)
 *
 * Description: This function returns the character at a given position in
 * the string or zero if the string doesn't have as many characters. Reports
 * an error if pos is out of bounds.
 */
function stringat:long(str:string, pos:long)
%{ /* pure */ /* unprivileged */ /* unmodified-fnargs */
	if (STAP_ARG_pos >= 0 && STAP_ARG_pos < strlen(STAP_ARG_str))
                STAP_RETURN(STAP_ARG_str[STAP_ARG_pos]);
	else {
		STAP_RETVALUE = 0;
#if STAP_COMPAT_VERSION >= STAP_VERSION(2,3) // PR15044
                STAP_ERROR("Position out of bounds");
#endif
	}
%}

/**
 * sfunction isinstr - Returns whether a string is a substring of another string
 *
 * @s1: string to search in
 * @s2: substring to find
 *
 * Description: This function returns 1 if string @s1 contains @s2,
 * otherwise zero. 
 */
function isinstr:long(s1:string,s2:string)
%{ /* pure */ /* unprivileged */ /* unmodified-fnargs */
	STAP_RETURN (strstr(STAP_ARG_s1,STAP_ARG_s2) != NULL);
%}

/**
 * sfunction strpos - Returns location of a substring within another string
 *
 * @s1: string to search in
 * @s2: substring to find
 *
 * Description: This function returns location of the first occurence of string
 * @s2 within @s1, namely the return value is 0 in case @s2 is a prefix of @s1.
 * If @s2 is not a substring of @s1, then the return value is -1.
 */
function strpos:long(s1:string,s2:string)
%{ /* pure */ /* unprivileged */ /* unmodified-fnargs */
	long pos = (long)strstr(STAP_ARG_s1,STAP_ARG_s2);
	STAP_RETURN ((pos != 0) ? (pos - (long)STAP_ARG_s1) : (-1));
%}

/**
 * sfunction text_str - Escape any non-printable chars in a string
 *
 * @input: the string to escape
 *
 * Description: This function accepts a string argument, 
 * and any ASCII characters that are not
 * printable are replaced by the corresponding escape sequence in the
 * returned string.
 */
function text_str:string(input:string)
%( runtime != "bpf" %? 
  %{ /* pure */ /* unprivileged */ /* unmodified-fnargs */
	  if (_stp_text_str(STAP_RETVALUE, STAP_ARG_input, 0, 0, 0, 0, 0) < 0) {
		  STAP_RETVALUE[0] = '\0';
	  }
  %}
%:
  %{  /* bpf */
      0xbf, 1, $input, -, -;  /* mov r1, $input */
      0x85, 0, 0, 0, -10;     /* call BPF_FUNC_TEXT_STR */
      0xbf, $$, 0, -, -;      /* return r0 */
  %}
%)

/**
 * sfunction text_strn - Escape any non-printable chars in a string
 *
 * @input: the string to escape
 * @len: maximum length of string to return (0 implies MAXSTRINGLEN)
 * @quoted: put double quotes around the string. If input string is
 * truncated it will have "..." after the second quote
 *
 * Description: This function accepts a string of designated length,
 * and any ASCII characters that are not
 * printable are replaced by the corresponding escape sequence in the
 * returned string.
 */
function text_strn:string(input:string, len:long, quoted:long)
%{ /* pure */ /* unprivileged */ /* unmodified-fnargs */
	int64_t len = clamp_t(int64_t, STAP_ARG_len, 0, MAXSTRINGLEN);
	if (_stp_text_str(
			STAP_RETVALUE, STAP_ARG_input, 0, len, STAP_ARG_quoted, 0, 0) < 0) {
		STAP_RETVALUE[0] = '\0';
	}
%}

/**
 * sfunction - str_replace Replaces all instances of a substring with another
 *
 * @prnt_str: the string to search and replace in
 * @srch_str: the substring which is used to search in @prnt_str string
 * @rplc_str: the substring which is used to replace @srch_str
 *
 * Description: This function returns the given string with
 * substrings replaced.
 */
function str_replace:string (prnt_str:string, srch_str:string, rplc_str:string)
%{ /* pure */ /* unprivileged */
	char *ptr = (char *)(uintptr_t)STAP_ARG_prnt_str;
	char *ptr_base = (char *)(uintptr_t)STAP_ARG_prnt_str;
	int strlen_srch_str = strlen(STAP_ARG_srch_str);

STAP_RETVALUE[0] = '\0';
	if(strlen_srch_str == 0) {
                STAP_RETURN (ptr_base);
	}

while((ptr = strstr(ptr, STAP_ARG_srch_str)) != NULL) {

*ptr = '\0';
		strlcat(STAP_RETVALUE, ptr_base, MAXSTRINGLEN);
		strlcat(STAP_RETVALUE, STAP_ARG_rplc_str, MAXSTRINGLEN);
		ptr = ptr + strlen_srch_str;
		ptr_base = ptr;
	}

strlcat(STAP_RETVALUE, ptr_base, MAXSTRINGLEN);
	return;
%}

/**
 * sfunction - strtol - Convert a string to a long
 *
 * @str: string to convert
 * @base: the base to use
 * 
 * Description: This function converts the string representation of a number to an integer. 
 * The @base parameter indicates the number base to assume for the string (eg. 16 for hex, 8 for octal, 2 for binary).
 */
function strtol:long(str:string, base:long)
%{ /* pure */ /* unprivileged */ /* unmodified-fnargs */
	STAP_RETURN(simple_strtol(STAP_ARG_str, NULL, STAP_ARG_base));
%}

/**
 * sfunction isdigit - Checks for a digit
 *
 * @str: string to check
 *
 * Description: Checks for a digit (0 through 9) as the first
 * character of a string.  Returns non-zero if true, and a zero if
 * false.
 */
function isdigit:long(str:string)
%{ /* pure */ /* unprivileged */ /* unmodified-fnargs */
 	STAP_RETURN(isdigit(STAP_ARG_str[0]));
%}

/**
 * sfunction string_quoted - Quotes a given string
 * @str: The kernel address to retrieve the string from
 *
 * Description: Returns the quoted string version of the given string,
 * with characters where any ASCII characters that are not printable
 * are replaced by the corresponding escape sequence in the returned
 * string. Note that the string will be surrounded by double quotes.
 */
function string_quoted:string (str:string)
%( runtime != "bpf" %? 
  %{ /* pure */ /* unmodified-fnargs */
    /* This can't fail, since the input string is already in stap context space. */
    (void) _stp_text_str(STAP_RETVALUE,
                         (char *)(uintptr_t)STAP_ARG_str,
                         MAXSTRINGLEN, MAXSTRINGLEN, 1, 0, 0);
  %}
%:
  %{  /* bpf */
      0xbf, 1, $str, -, -;  /* mov r1, $input */
      0x85, 0, 0, 0, -11;     /* call BPF_FUNC_STRING_QUOTED */
      0xbf, $$, 0, -, -;      /* return r0 */
  %}
%)

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