small refactor to vsnprintf

1 files changed, 112 insertions, 88 deletions

diff --git a/lib/printf.c b/lib/printf.c
index 4e64d7b..b96c616 100644
--- a/lib/printf.c
+++ b/lib/printf.c
@@ -22,7 +22,6 @@ convert_as_int(
         char *str,
         size_t size,
         int stri,
-        int field_width,
         uintmax_t value,
         int radix,
         int unsign)
@@ -37,17 +36,79 @@ convert_as_int(
     for(uintmax_t i = value; i != 0; i /= radix) digits++;
     if(value == 0) digits++;
 
-    if(field_width < digits) field_width = digits;
     for(uintmax_t i = value, digiti = 0; digiti < digits; i /= radix) {
         char i_mod = (char)(i % radix);
-        int stri_digiti = stri + (field_width - digiti) - 1;
+        int stri_digiti = stri + (digits - digiti) - 1;
 
         SPRINTF_PUTC(str, size, stri_digiti,
                 (i_mod > 9 ? (i_mod + 'a' - 10) : (i_mod + '0')));
         digiti++;
     }
 
-    return field_width + (stri - ostri) + 1;
+    return digits;
+}
+
+enum printf_state
+{
+    FSTATE_DIRECT = 0,
+    FSTATE_CONVERT
+};
+
+static int
+s_convert_string(char *str, size_t size, va_list ap, size_t stri)
+{
+    const char *strarg = va_arg(ap, const char*);
+    for(const char *strargc = strarg; *strargc; strargc++) {
+        SPRINTF_PUTC(str, size, stri, *strargc);
+    }
+    return stri;
+}
+
+static int
+s_convert_int(char *str, size_t size, va_list ap, size_t stri,
+              int fw, char fp, int typelen, int radix, int usign, int caps)
+{
+    char num_buf[64];
+    uintmax_t value = 0;
+    switch(typelen) {
+        case 1: value = (uintmax_t)(int8_t)va_arg(ap, int); break;
+        case 2: value = (uintmax_t)(int16_t)va_arg(ap, int); break;
+        default:
+        case 4: value = (uintmax_t)va_arg(ap, unsigned int); break;
+        case 8: value = (uintmax_t)va_arg(ap, uintmax_t); break;
+    }
+    size_t pad_stri = stri;
+
+    int advance = convert_as_int(num_buf, 64, 0, value, radix, usign);
+    if(caps) {
+        for(int i = 0; i < advance; i++) {
+            num_buf[i] = c_toupper(num_buf[i]);
+        }
+    }
+
+    int pad_diff = fw - advance;
+    for(int i = 0; i < pad_diff; i++) {
+        SPRINTF_PUTC(str, size, stri, fp);
+    }
+    for(int i = 0; i < advance; i++) {
+        SPRINTF_PUTC(str, size, stri, num_buf[i]);
+    }
+
+    return stri;
+}
+
+int
+s_convert_path(char *str, size_t size, va_list ap, size_t stri)
+{
+    uint16_t *obj_path = va_arg(ap, uint16_t*);
+    size_t obj_pathlen = va_arg(ap, size_t);
+    for(size_t i = 0; i < obj_pathlen; i++) {
+        uint16_t subdir = obj_path[i];
+        int advance = convert_as_int(str, size, stri, subdir, 10, 1);
+        stri += advance;
+        SPRINTF_PUTC(str, size, stri, '/');
+    }
+    return stri;
 }
 
 int 
@@ -56,97 +117,60 @@ vsnprintf(
         const char *fmt, va_list ap)
 {
     int stri = 0;
+    int state = FSTATE_DIRECT;
+
     for(const char *fmtc = fmt; *fmtc; fmtc++) {
-        if(*fmtc != '%') {
+        if(state == FSTATE_DIRECT) {
+            if(*fmtc == '%') {
+                state = FSTATE_CONVERT;
+                continue;
+            }
             SPRINTF_PUTC(str, size, stri, *fmtc);
-            continue;
-        }
-        fmtc++;
-
-        //TODO: other format specifiers.
-        int field_width = 0;
-        char field_pad = ' ';
+        }else {
+            int field_width = 0;
+            char field_pad = ' ';
 
-        int lenspec = 4;
+            int lenspec = 4;
         
-        int radix = 10;
-        int unsign = 0;
-        int caps = 0;
-        switch(*fmtc) {
-            case 's':
-                goto string_conversion;
-            case 'b':
-                radix = 2;
-                goto int_conversion;
-                break;
-            case 'o':
-                radix = 8;
-                goto int_conversion;
-                break;
-            case 'p':
-                lenspec = sizeof(uintptr_t);
-                field_width = lenspec * 2;
-                field_pad = '0';
-            case 'X':
-                caps = 1;
-            case 'x':
-                unsign = 1;
-                radix = 16;
-                goto int_conversion;
-                break;
-            case 'u':
-                unsign = 1;
-            case 'd':
-            case 'i':
-                goto int_conversion;
-                break;
-            /*custom formatters for jove.*/
-            case 'P':
-                goto path_conversion;
-                break;
-        }
-string_conversion:
-        {
-            const char *strarg = va_arg(ap, const char*);
-            for(const char *strargc = strarg; *strargc; strargc++) {
-                SPRINTF_PUTC(str, size, stri, *strargc);
-            }
-        } continue;
-int_conversion: 
-        {
-            uintmax_t value = 0;
-            switch(lenspec) {
-                case 1: value = (uintmax_t)(int8_t)va_arg(ap, int); break;
-                case 2: value = (uintmax_t)(int16_t)va_arg(ap, int); break;
-                default:
-                case 4: value = (uintmax_t)va_arg(ap, unsigned int); break;
-                case 8: value = (uintmax_t)va_arg(ap, uintmax_t); break;
-            }
-            size_t pad_stri = stri;
-            for(size_t i = 0; i < field_width; i++) {
-                SPRINTF_PUTC(str, size, pad_stri, field_pad);
-            }
+            int radix = 10;
+            int unsign = 0;
+            int caps = 0;
 
-            int advance = convert_as_int(str, size, stri, field_width, value, radix, unsign);
-            if(caps && str) {
-                for(int i = 0; i < advance; i++) {
-                    int stra = stri + i;
-                    if(stra < size) str[stra] = c_toupper(str[stra]);
+            if(state == FSTATE_CONVERT) {
+                switch(*fmtc) {
+                    case 's':
+                        stri = s_convert_string(str, size, ap, stri);
+                        break;
+                    case 'b':
+                        stri = s_convert_int(str, size, ap, stri, field_width, field_pad, lenspec, 2, 1, 0);
+                        break;
+                    case 'o':
+                         stri = s_convert_int(str, size, ap, stri, field_width, field_pad, lenspec, 8, 0, 0);
+                        break;
+                    case 'p':
+                        lenspec = sizeof(uintptr_t);
+                        field_width = lenspec * 2;
+                        field_pad = '0';
+                    case 'X':
+                        caps = 1;
+                    case 'x':
+                        unsign = 1;
+                        stri = s_convert_int(str, size, ap, stri, field_width, field_pad, lenspec, 16, unsign, caps);
+                        break;
+                    case 'u':
+                        unsign = 1;
+                    case 'd':
+                    case 'i':
+                        stri = s_convert_int(str, size, ap, stri, field_width, field_pad, lenspec, 10, unsign, caps);
+                        break;
+                    /*custom formatters for jove.*/
+                    case 'P':
+                        stri = s_convert_path(str, size, ap, stri);
+                        break;
                 }
             }
-            stri += advance;
-        } continue;
-path_conversion:
-        {
-            uint16_t *obj_path = va_arg(ap, uint16_t*);
-            size_t obj_pathlen = va_arg(ap, size_t);
-            for(size_t i = 0; i < obj_pathlen; i++) {
-                uint16_t subdir = obj_path[i];
-                int advance = convert_as_int(str, size, stri, 3, subdir, 10, 1);
-                stri += advance;
-                SPRINTF_PUTC(str, size, stri, '/');
-            }
-        } continue;
+            state = FSTATE_DIRECT;
+        }
     }
     if(str && stri < size) str[stri] = 0;
     return stri;