Replace os_regex with RE2 in the Agent

[cborla]

Parent issue:

• Migrate Syscollector module to new agent

Description

Deprecate or remove the non-standard os_regex library and replace it with the standard RE2 library. This will improve compatibility and long-term maintainability of the Inventory module.

Tasks

• Check if 5.0's agent suits all the conditions to use RE2.
• Identify where os_regex is used in the codebase.
• Replace os_regex with RE2.
• Refactor the affected code for compatibility.
• Test the implementation to ensure functionality.

Testing tasks

• Ensure all unit tests pass after the replacement.
• Test compatibility on all supported platforms.

[LucioDonda]

Update 16/09/2024

• Check if 5.0's agent suits all the conditions to use RE2.:
  • based on some analysis it can be used without any problem, from c++14 it works. included in vcpk and basic examples checked.
  • Additional performance check here
• Identify where os_regex is used in the codebase:
  • OS_PRegex: os_string (1) and maybe in the configurations parser.
  • w_regexec: version_op (7) in the future if used maybe on remoted_op and wdb_global
  • w_sql_regex: Not used since 4.8.0 .
• Starting Replacement generating based UTs to be used for check In the newest version.

[LucioDonda]

Update 17/09/2024

• Starting migration.
  • working on some issues regarding compilation of C and C++ alongside

[LucioDonda]

Update 18/09/2024

After the team daily I came across that I was pointing to the wrong file. New analysis was made:

1. int OSRegex_Compile(const char *pattern, OSRegex *reg, int flags);
   Brief: Compile a regular expression to be used later
   Usage:

   • expression.c (1)
     Tests (wrap):
   • test_expression (4)
   • github unit tests (8)

2. const char *OSRegex_Execute(const char *str, OSRegex *reg) __attribute__((nonnull(2)));
   Brief: Compares an already compiled OSRegex regular expression with a string
   Usage:

   • Internal Only (os_regex.c and os_regex_execute.c)
     Tests (wrap):
   • wm_github

3. const char *OSRegex_Execute_ex(const char *str, OSRegex *reg, regex_matching *regex_match) __attribute__((nonnull(2))); Brief: Compares an already compiled OSRegex regular expression with a string (+ struct for pattern matches)
   Usage:

   • expression.c
   • • Internal
       Tests:
   • test_expression
   • wraps schedule_scan , github

4. void OSRegex_FreePattern(OSRegex *reg);
   Brief: Release all the memory created by the compilation/execution phases
   Usage:

   • expression.c
   • Internal
     Tests:
   • wrap: github

5. int OS_Regex(const char *pattern, const char *str);
   Brief: wrapper around the compile/execute functions. It should only be used when the pattern is only going to be used once.
   Usage:

   • logcollector (1)
   • common (rootcheck dir) (2)
   • wm_sca (1)

6. int OSMatch_Compile(const char *pattern, OSMatch *reg, int flags);
   Brief: Compile a pattern to be used later.
   Usage:

   • expression.c
     Tests:
   • fim (test_create_db, test_fim_diff_changes, test_registry)

7. int OSMatch_Execute(const char *str, size_t str_len, OSMatch *reg);
   Brief: Compare an already compiled pattern with a not NULL string.
   Usage:

   • expression.c
   • fim (create_db, fim_diff_changes, registry)
   • rootcheck.c

8. void OSMatch_FreePattern(OSMatch *reg);
   Brief: Release all the memory created by the compilation/execution phases */
   Usage:

   • expression.c
     Tests:
   • fim (create_db, registry)

9. int OS_Match2(const char *pattern, const char *str) __attribute__((nonnull(2)));
   Brief: No Info
   Usage:

   • rootcheck (common)
   • wm_sca

10) int OS_WordMatch(const char *pattern, const char *str) __attribute__((nonnull));
Brief: Searches for pattern in the string
OS_Match ??

11. char **OS_StrBreak(char match, const char *str, size_t size);
    Brief: Split a string into multiples pieces, divided by a char "match".
    Usage:
    • debug_op (1)
    • schedule_scan (3)
    • string_op (1)
    • version_op
    • config.c
      wm_sca

12) size_t OS_StrHowClosedMatch(const char *str1, const char *str2);
Brief: Returns the number of characters that both strings have in similar

13. int OS_StrStartsWith(const char *str, const char *pattern) __attribute__((nonnull));
    Brief: Verifies if a string starts with the provided pattern.

14. int OS_StrIsNum(const char *str);
    Brief: Checks if a specific string is numeric (like "129544") */
    Usage:

    • Schedule_scan
      Tests:
    • test_ schedule scan

15. void OSRegex_free_regex_matching (regex_matching *reg);
    Brief: Free memory of regex_matching struct
    Usage:

    • expression.c (4)
    • validate_op

[cborla]

I will move this issue to backlog again because it has no priority.