Add doc

doc/funcref.sgml

@@ -780,6 +780,7 @@ communication, see also <tt>testcode/lib/ser-test.c</tt>.
 <item><ref id="strqtok" name="strqtok">
 <item><ref id="strrchr" name="strrchr">
 <item><ref id="strspn" name="strspn">
+<item><ref id="strcasestr" name="strcasestr">
 <item><ref id="strstr" name="strstr">
 <item><ref id="strtok" name="strtok">
 <item><ref id="strxfrm" name="strxfrm">
@@ -7899,22 +7900,47 @@ be used in presence of a prototype.
 </quote>
 
 
-<sect1>strstr<label id="strstr"><p>
+<sect1>strcasestr<label id="strcasestr"><p>
 
 <quote>
 <descrip>
-<tag/Function/Find a substring.
+<tag/Function/Find a substring, case-insensitive.
 <tag/Header/<tt/<ref id="string.h" name="string.h">/
-<tag/Declaration/<tt/char* __fastcall__ strstr (const char* str, const char* substr);/
-<tag/Description/<tt/strstr/ searches for the first occurrence of the string
-<tt/substr/ within <tt/str/. If found, it returns a pointer to the copy,
-otherwise it returns <tt/NULL/.
+<tag/Declaration/<tt/char* __fastcall__ strcasestr (const char* str, const char* substr);/
+<tag/Description/<tt/strcasestr/ searches for the first occurrence of the string
+<tt/substr/ within <tt/str/. If found, it returns a pointer to the start of the
+match in <tt/str/, otherwise it returns <tt/NULL/.
 <tag/Notes/<itemize>
 <item>The function is only available as fastcall function, so it may only
 be used in presence of a prototype.
 </itemize>
 <tag/Availability/ISO 9899
 <tag/See also/
+<ref id="strstr" name="strstr">,
+<ref id="strcspn" name="strcspn">,
+<ref id="strspn" name="strspn">
+<tag/Example/None.
+</descrip>
+</quote>
+
+
+<sect1>strstr<label id="strstr"><p>
+
+<quote>
+<descrip>
+<tag/Function/Find a substring, case-sensitive.
+<tag/Header/<tt/<ref id="string.h" name="string.h">/
+<tag/Declaration/<tt/char* __fastcall__ strstr (const char* str, const char* substr);/
+<tag/Description/<tt/strstr/ searches for the first occurrence of the string
+<tt/substr/ within <tt/str/. If found, it returns a pointer to the start of the
+match in <tt/str/, otherwise it returns <tt/NULL/.
+<tag/Notes/<itemize>
+<item>The function is only available as fastcall function, so it may only
+be used in presence of a prototype.
+</itemize>
+<tag/Availability/ISO 9899
+<tag/See also/
+<ref id="strcasestr" name="strcasestr">,
 <ref id="strcspn" name="strcspn">,
 <ref id="strspn" name="strspn">
 <tag/Example/None.

libsrc/common/strcasestr.s

@@ -0,0 +1,95 @@
+;
+; Ullrich von Bassewitz, 11.12.1998
+;
+; char* strcasestr (const char* haystack, const char* needle);
+;
+
+        .export         _strcasestr
+        .import         popptr1, return0, tolowerdirect
+        .importzp       ptr1, ptr2, ptr3, ptr4, tmp1, tmp2, tmp3, tmp4
+        .include        "ctype.inc"
+
+        .segment "LOWCODE"
+
+_strcasestr:
+        sta     ptr2            ; Save needle
+        stx     ptr2+1
+        sta     ptr4            ; Setup temp copy for later
+
+        jsr     popptr1         ; Get haystack to ptr1
+
+; If needle is empty, return haystack
+
+        ; ldy     #$00            Y=0 guaranteed by popptr1
+        lda     (ptr2),y        ; Get first byte of needle
+        beq     @Found          ; Needle is empty --> we're done
+
+; Search for the beginning of the string (this is not an optimal search
+; strategy [in fact, it's pretty dumb], but it's simple to implement).
+
+        jsr     tolowerdirect   ; Lowercase
+        sta     tmp1            ; Save start of needle
+@L1:    lda     (ptr1),y        ; Get next char from haystack
+        beq     @NotFound       ; Jump if end
+
+        jsr     tolowerdirect   ; Lowercase
+        cmp     tmp1            ; Start of needle found?
+        beq     @L2             ; Jump if so
+        iny                     ; Next char
+        bne     @L1
+        inc     ptr1+1          ; Bump high byte
+        bne     @L1             ; Branch always
+
+; We found the start of needle in haystack
+
+@L2:    tya                     ; Get offset
+        clc
+        adc     ptr1
+        sta     ptr1            ; Make ptr1 point to start
+        bcc     @L3
+        inc     ptr1+1
+
+; ptr1 points to the start of needle in haystack now. Setup temporary pointers for the
+; search. The low byte of ptr4 is already set.
+
+@L3:    sta     ptr3
+        lda     ptr1+1
+        sta     ptr3+1
+        lda     ptr2+1
+        sta     ptr4+1
+        ldy     #1              ; First char is identical, so start on second
+
+; Do the compare
+
+@L4:    lda     (ptr4),y        ; Get char from needle
+        beq     @Found          ; Jump if end of needle (-> found)
+
+        jsr     tolowerdirect   ; Lowercase
+        sta     tmp2
+
+        lda     (ptr3),y        ; Compare with haystack
+
+        jsr     tolowerdirect   ; Lowercase
+        cmp     tmp2
+        bne     @L5             ; Jump if not equal
+        iny                     ; Next char
+        bne     @L4
+        inc     ptr3+1
+        inc     ptr4+1          ; Bump hi byte of pointers
+        bne     @L4             ; Next char (branch always)
+
+; The strings did not compare equal, search next start of needle
+
+@L5:    ldy     #1              ; Start after this char
+        bne     @L1             ; Branch always
+
+; We found the start of needle
+
+@Found: lda     ptr1
+        ldx     ptr1+1
+        rts
+
+; We reached end of haystack without finding needle
+
+@NotFound:
+        jmp     return0         ; return NULL

libsrc/common/strstr.s

@@ -4,20 +4,11 @@
 ; char* strstr (const char* haystack, const char* needle);
 ;
 
-        .export         _strstr, _strcasestr
-        .import         popptr1, return0, tolowerdirect
-        .importzp       ptr1, ptr2, ptr3, ptr4, tmp1, tmp2
-
-maybe_lower:                    ; Lowercase char in A if needed
-        jmp     tolowerdirect   ; patched on entry with either JMP or RTS
+        .export         _strstr
+        .import         popptr1
+        .importzp       ptr1, ptr2, ptr3, ptr4, tmp1
 
 _strstr:
-        ldy     #$60            ; RTS
-        bne     :+
-_strcasestr:
-        ldy     #$4C            ; JMP absolute
-:       sty     maybe_lower
-
         sta     ptr2            ; Save needle
         stx     ptr2+1
         sta     ptr4            ; Setup temp copy for later
@@ -33,12 +24,9 @@ _strcasestr:
 ; Search for the beginning of the string (this is not an optimal search
 ; strategy [in fact, it's pretty dumb], but it's simple to implement).
 
-        jsr     maybe_lower     ; Lowercase if needed
         sta     tmp1            ; Save start of needle
 @L1:    lda     (ptr1),y        ; Get next char from haystack
         beq     @NotFound       ; Jump if end
-
-        jsr     maybe_lower     ; Lowercase if needed
         cmp     tmp1            ; Start of needle found?
         beq     @L2             ; Jump if so
         iny                     ; Next char
@@ -55,7 +43,7 @@ _strcasestr:
         bcc     @L3
         inc     ptr1+1
 
-; ptr1 points to the start of needle in haystack now. Setup temporary pointers for the
+; ptr1 points to the start of needle now. Setup temporary pointers for the
 ; search. The low byte of ptr4 is already set.
 
 @L3:    sta     ptr3
@@ -69,14 +57,7 @@ _strcasestr:
 
 @L4:    lda     (ptr4),y        ; Get char from needle
         beq     @Found          ; Jump if end of needle (-> found)
-
-        jsr     maybe_lower     ; Lowercase if needed
-        sta     tmp2
-
-        lda     (ptr3),y        ; Compare with haystack
-
-        jsr     maybe_lower     ; Lowercase if needed
-        cmp     tmp2
+        cmp     (ptr3),y        ; Compare with haystack
         bne     @L5             ; Jump if not equal
         iny                     ; Next char
         bne     @L4
@@ -98,4 +79,6 @@ _strcasestr:
 ; We reached end of haystack without finding needle
 
 @NotFound:
-        jmp     return0         ; return NULL
+        lda     #$00            ; return NULL
+        tax
+        rts