strtok and some changes to string.h

code/printf.h

@@ -75,6 +75,12 @@ inline static int FMT_FUNC_NAME (void *ctx, OutputFunc out, const FMT_CHAR_TYPE
 
         FMT_CHAR_TYPE ch = *fmt++;
         switch (ch) {
+            case 'c': {
+                const char chr = va_arg(args, int);
+                out(ctx, 1, &chr);
+                full_length ++;
+                break;
+            }
             case 's': {
                 const FMT_CHAR_TYPE *str = va_arg(args, FMT_CHAR_TYPE*);
                 size_t len = FMT_STRLEN_S(str, precision ? precision : SIZE_MAX);

code/string.c

@@ -20,8 +20,7 @@ void *memcpy(void *restrict s1, const void *restrict s2, size_t n) {
     return s1;
 }
 
-void *memmove(void *s1, const void *s2, size_t n)
-{
+void *memmove(void *s1, const void *s2, size_t n) {
     void *buffer = malloc(n);
     memcpy(buffer, s2, n);
     memcpy(s1, buffer, n);
@@ -29,16 +28,7 @@ void *memmove(void *s1, const void *s2, size_t n)
     return s1;
 }
 
-void *memset(void *s, int c, size_t n) {
-    byte *restrict buf = s;
-    while (n--) {
-        *buf++ = c;
-    }
-    return s;
-}
-
-char *strcpy(char *restrict s1, const char *restrict s2)
-{
+char *strcpy(char *restrict s1, const char *restrict s2) {
     while(*s2 != 0) {
         *s1++ = *s2++;
     }
@@ -46,25 +36,26 @@ char *strcpy(char *restrict s1, const char *restrict s2)
     return s1;
 }
 
-char *strncpy(char *restrict s1, const char *restrict s2, size_t n)
-{
-    while(n-->0 && *s2 != 0) {
+char *strncpy(char *restrict s1, const char *restrict s2, size_t n) {
+    size_t i = 0;
+    for(; i < n && *s2 != 0; ++ i) {
         *s1++ = *s2++;
     }
-    while(n-->0) {
+    for(; i < n; ++i) {
         *s1++ = 0;
     }
     return s1;
 }
 
 
-char *strncat(char *restrict s1, const char *restrict s2, size_t n)
-{
+char *strcat(char *restrict s1, const char *restrict s2) {
     size_t start = strlen(s1);
-    for(size_t i = 0; i != n && *s2 != 0; ++i) {
-        s1[start+i] = s2[i];
+    return strcpy(s1+start, s2);
 }
-    s1[start+n] = 0;
+
+char *strncat(char *restrict s1, const char *restrict s2, size_t n) {
+    size_t start = strlen(s1);
+    strncpy(s1+start, s2, n);
     return s1;
 }
 
@@ -78,6 +69,14 @@ int memcmp(const void *s1, const void *s2, size_t n) {
     return 0;
 }
 
+void *memset(void *s, int c, size_t n) {
+    byte *restrict buf = s;
+    while (n--) {
+        *buf++ = c;
+    }
+    return s;
+}
+
 int strcmp(const char *s1, const char *s2) {
     int diff;
     do {
@@ -86,8 +85,7 @@ int strcmp(const char *s1, const char *s2) {
     return diff;
 }
 
-int strncmp(const char *s1, const char *s2, size_t n)
-{
+int strncmp(const char *s1, const char *s2, size_t n) {
     int diff = 0;
     size_t i = 0;
     if(n != 0) do {
@@ -96,15 +94,13 @@ int strncmp(const char *s1, const char *s2, size_t n)
     return diff;
 }
 
-// fuck locales
-int strcoll(const char *s1, const char *s2)
-{
+int strcoll(const char *s1, const char *s2) {
     return strcmp(s1, s2);
 }
 
-// fuck bad implementation of strcoll
-size_t strxfrm(char *restrict s1, const char *restrict s2, size_t n)
-{
+// TODO: I don't quite understand the intent nor use behind this function
+// so I'm just going to ignore locales for now.
+size_t strxfrm(char *restrict s1, const char *restrict s2, size_t n) {
     size_t len = strlen(s2);
     if(s1 != NULL && n != 0) {
         for(size_t i = 0; i != n; ++i) {
@@ -114,39 +110,47 @@ size_t strxfrm(char *restrict s1, const char *restrict s2, size_t n)
     return len;
 }
 
-void *memchr(const void *ptr, int c, size_t n)
-{
-    const byte *s = ptr;
-    size_t i = 0;
-    for(; i != n && *s != c; ++i, ++s) {
-        ++s;
+void *memchr(const void *ptr, int c, size_t n) {
+    const char *s = ptr;
+    for(size_t i = 0; i != n; ++i) {
+        if(s[i] == c) {
+            // Casting away const because clang warnings
+            return (void *)(s+i);
         }
-    if(i == n) return NULL;
-    return (void *)s; // fuck clang
+    }
+    return NULL;
 }
 
-char *strchr(const char *s, int c)
-{
-    while(*s && *s != c) ++s;
-    if(*s != c) return NULL;
-    return (void *)s; // fuck clang
+char *strchr(const char *s, int c) {
+    do {
+        if(*s == c) return (char *)s;
+    } while(*s++);
+    return NULL;
 }
 
-size_t strcspn(const char *s1, const char *s2)
-{
+size_t strspn(const char *s1, const char *s2) {
     size_t i = 0;
-    while(*s1) {
-        if(strchr(s2, *s1) != NULL) {
+    for(; *s1; ++s1) {
+        if(strchr(s2, *s1) == NULL) {
             break;
         }
-        ++s1;
         ++i;
     }
     return i;
 }
 
-char *strpbrk(const char *s1, const char *s2)
-{
+size_t strcspn(const char *s1, const char *s2) {
+    size_t i = 0;
+    for(; *s1; ++s1) {
+        if(strchr(s2, *s1) != NULL) {
+            break;
+        }
+        ++i;
+    }
+    return i;
+}
+
+char *strpbrk(const char *s1, const char *s2) {
     while(*s1) {
         if(strchr(s2, *s1) == NULL) {
             break;
@@ -156,26 +160,47 @@ char *strpbrk(const char *s1, const char *s2)
     return (char *)s1;
 }
 
-char *strstr(const char *s1, const char *s2)
-{
-    if(!*s2) return (char *)s1;
+char *strrchr(const char *s, int c) {
+    char const *last = NULL;
+    for(; *s != 0; ++s) {
+        if(*s == c) last = s;
+    }
+    return (char *)last;
+}
+
+char *strstr(const char *s1, const char *s2) {
+    if(*s2 == 0) return (char *)s1;
     size_t len = strlen(s2);
-    while(*s1 != 0) {
-        bool match = true;
-        for(size_t i = 0; i != len; ++i) {
-            if(!*s1 || s1[i] != s2[i]) {
-                match = false;
-                break;
-            }
-        }
-        ++s1;
-        if(match) return (char *)s1;
+    for(; *s1 != 0; ++s1) {
+        if(strncmp(s1, s2, len) == 0) return (char *)s1;
     }
     return NULL;
 }
 
-char *strerror(int errnum)
-{
+// TODO: there may be restrict-related UB
+char *strtok(char *restrict s1, const char *restrict s2) {
+    static char *restrict str;
+    if(s1 != NULL) str = s1;
+    if(str == NULL) return NULL;
+
+    size_t junk_len = strspn(str, s2);
+    char *tok_start = str+junk_len;
+    if(*tok_start == 0) {
+        str = NULL;
+        return NULL;
+    }
+
+    size_t tok_len = strcspn(str, s2);
+
+    char *tok_end = tok_start + tok_len;
+    *tok_end = 0;
+    str = tok_end+1;
+
+    return tok_start;
+}
+
+
+char *strerror(int errnum) {
     switch(errnum) {
         case 0:      return "No errors";
         case EDOM:   return "Value is out of domain of the function";

inc/string.h

@@ -1,6 +1,11 @@
 
 #pragma once
 
+// Technically all we should have here is typedef for size_t.
+// but I can't get that without macro shittery so
+// for now I'm just doing this, which is not quite correct
+#include <stddef.h>
+
 #if !defined(NULL)
     #define NULL ((void *)0)
 #endif

test/test.c

@@ -7,15 +7,28 @@
 #include <stdbool.h>
 #include <inttypes.h>
 
+#include <string.h>
 #include <signal.h>
 
-void onabort(int a) {
-    printf("I don't want to live anymore\n");
-    exit(-69);
+int test() {
+    static int a = 2;
+    a += 1;
+    return a;
 }
 
 int main(int argc, char** argv) {
-    signal(SIGABRT, onabort);
-    assert(0 != 0);
+    test();
+    char input[] = "A bird came down the walk";
+    printf("Parsing the input string '%s'\n", input);
+    char *token = strtok(input, " ");
+    while(token) {
+        printf("%s\n", token);
+        token = strtok(NULL, " ");
+    }
+ 
+    printf("Contents of the input string now: '");
+    for(size_t n = 0; n < sizeof input; ++n)
+        input[n] ? printf("%c", input[n]) : printf("\\0");
+    printf("'");
     return 0;
 }