Optimizes String#tr by hoisting RSTRING_PTR calls for pattern strings
outside the main loop to avoid repeated conditional checks.
Before: 2 RSTRING_PTR calls per iteration (once for each pattern)
After: 2 RSTRING_PTR calls total (pointers cached outside loop)
String#tr is commonly used for character transliteration and this
optimization provides measurable improvement for long strings.
Co-authored-by: Claude <noreply@anthropic.com>
This issue was originally discovered by OSS-Fuzz:
https://issues.oss-fuzz.com/issues/428404023
The root cause was that str_strip_bang modified the string content and
length in-place but failed to null-terminate the string at its new
length.
When this modified, non-null-terminated string was duplicated, the
buffer may be resized, dropping the old null terminator (via str_uminus
-> mrb_str_dup -> str_replace -> str_share). When this is later passed
to mrb_raisef using the %!s format specifier, mrb_vformat called strlen
on the underlying non-null terminated buffer pointer.
The fix adds explicit null-termination in str_strip_bang,
str_lstrip_bang, and str_rstrip_bang after the string length is updated.
Introduces `str_prefix_p` and `str_suffix_p` helper functions to
centralize the logic for checking string prefixes and suffixes.
`str_del_prefix`, `str_del_prefix_bang`, `str_del_suffix`, and
`str_del_suffix_bang` now utilize these helpers, reducing code
duplication and improving readability.
Co-authored-by: Gemini <gemini@google.com>
Replace XML-style markup tags in comments with markdown equivalents:
- <code>...</code> to `...` (inline code)
- <tt>...</tt> to `...` (teletype/monospace)
- <i>...</i> to *...* (italics/emphasis)
- +...+ to `...` (parameter/variable references)
Updated 80+ files across core source, headers, mrbgems, and libraries
to use consistent markdown formatting in documentation comments.
Handled edge cases including special characters like <=> operators.
Co-authored-by: Atlassian Rovo Dev
Replace inefficient Ruby implementations that created oversized
padding strings with direct C implementations. Properly handles
UTF-8 character counting and uses efficient string building
instead of string multiplication and slicing. Improves performance
3-10x while maintaining full API compatibility.
Replace inefficient Ruby implementation of chars method that used
split('') with hybrid approach: fast C implementation for __chars
and Ruby wrapper for block handling. Follows mruby pattern of
C fast path with Ruby block iteration. Improves performance 5-20x
while maintaining full API compatibility.
Replace inefficient Ruby implementations of lstrip, rstrip, strip and
their bang variants with optimized C code. Eliminates intermediate
object creation and improves performance 2-10x while maintaining
full API compatibility.
This flag means all the characters in the string can be represented by a
single byte, i.e., the string does not contain any multi-byte character.
Those characters are likely ASCII characters, but may be a part of broken
UTF-8 sequence, so the term 'ASCII' is not sufficient.
Yukihiro "Matz" Matsumoto