diff --git a/code/errno.c b/code/errno.c
new file mode 100644
index 0000000..cdb2993
--- /dev/null
+++ b/code/errno.c
@@ -0,0 +1,4 @@
+
+#include <errno.h>
+
+int errno;
diff --git a/code/stdlib/conv.c b/code/stdlib/conv.c
index f40392d..582c540 100644
--- a/code/stdlib/conv.c
+++ b/code/stdlib/conv.c
@@ -4,10 +4,18 @@
 #include <stdbool.h>
 #include <limits.h>
 #include <errno.h>
+#include <math.h>
 
-// TODO: strto*: locale-based parsing for integers
-// TODO: i made a function that parses longs and i'm fucken
-// tired. someone make float parsing :kekw:
+// TODO: strto*: locale-based parsing
+// TODO: correctly rounded base 16 floats parsing
+
+// Call me weak if you want but I'm actually too lazy to type
+// them out every time, also they take up a lot of horiz space.
+typedef long long intll;
+typedef long intl;
+typedef unsigned long long intull;
+typedef unsigned long intul;
+typedef unsigned intu;
 
 #define inrange(start, c, end) ((start) <= (c) && (c) <= (end))
 
@@ -28,8 +36,18 @@ static bool isbase(int c, int base) {
     return val < base;
 }
 
+static bool strprefix_i(char const *restrict str, char const *restrict prefix) {
+    while(*prefix != 0) {
+        if(*str == 0) break;
+        if(toupper(*str) != toupper(*prefix)) return false;
+        ++prefix;
+        ++str;
+    }
+    return true;
+}
+
 // Called only when isbase(c, base) for some base in range
-static long todigitl(int c) {
+static long todigit(int c) {
     int val;
     if(isdigit(c)) {
         val = c-'0';
@@ -43,92 +61,255 @@ static long todigitl(int c) {
     return val;
 }
 
-long
-strtol(const char *restrict nptr, char **restrict endptr, int inbase) {
-    if(!inrange(0, inbase, 36)) {
-        *endptr = NULL;
-        return 0;
+static intull strtoi_generic(const char *restrict nptr,
+                             char **restrict endptr,
+                             int inbase,
+                             intl *coefptr,
+                             intull int_max) {
+    const char *restrict str = nptr;
+    intull value = 0;
+    int digits_read = 0;
+    bool is_signed = (coefptr != NULL);
+    // Find max{abs(int)}. Signed integers have negative,
+    // whose absolute value is 1 bigger than int_max.
+    intull int_abs_max = int_max;
+    if(is_signed) {
+        ++int_abs_max;
     }
+    if(!inrange(0, inbase, 36)) {
+        goto finish;
+    }
+    intull base = (intull)inbase;
     // Skip space on the beginning
-    while(isspace(*nptr)) {
-        ++nptr;
+    while(isspace(*str)) {
+        ++str;
     }
     // Parse sign
-    long coef = 1;
-    if(*nptr == '-') {
-        coef = -1;
-        ++nptr;
+    intl coef = 1;
+    if(is_signed) {
+        if(*str == '-') {
+            coef = -1;
+            ++str;
+        }
     }
-    if(*nptr == '+') {
-        ++nptr;
+    if(*str == '+') {
+        ++str;
     }
-    unsigned long base = (unsigned long)inbase;
-    unsigned long value = 0;
     // See if we need to parse base in C-like format
-    if(*nptr == '0' && *(nptr+1) == 'x') {
-        ++nptr;
+    // then set the base accordingly
+    if(strprefix_i(str, "0X")) {
+        ++str;
         if(base == 16 || base == 0) {
-            ++nptr;
+            ++str;
             base = 16;
         }
         else {
-            value = 0;
-            goto end;
+            goto finish;
         }
     }
-    else if(*nptr == '0') {
-        ++nptr;
+    else if(*str == '0') {
+        ++str;
+        ++digits_read;
         if(base == 8 || base == 0) {
             base = 8;
         }
     }
-    while(isbase(*nptr, (int)base)) {
-        unsigned long digit = (unsigned long)todigitl(*nptr);
-        if(value > (ULONG_MAX - digit)/base) {
-            errno = ERANGE;
-            value = 0;
-            goto end;
+    // Parse the string of digits in the given base. If the value
+    // exceeds abs(int_min) we exit with range error.
+    while(isbase(*str, (int)base)) {
+        intull digit = (intull)todigit(*str);
+        if(value > (int_abs_max - digit)/base) {
+            goto error_out_of_range;
         }
         value = base*value + digit;
-        ++nptr;
+        ++str;
+        ++digits_read;
     }
-    unsigned long max_modulo = (unsigned long)LONG_MAX+1;
-    if(value > max_modulo) {
-        errno = ERANGE;
+    // We only allow the modulo of value equal to abs(int_min) if it is
+    // preceeded by the minus sign.
+    if(is_signed) {
+        if(value == int_abs_max && coef != -1) {
+            goto error_out_of_range;
+        }
+    }
+    goto finish;
+    error_out_of_range:
+    // Skip the remainder of the subject string
+    while(isbase(*str, (int)base)) {
+        ++str;
+    }
+    errno = ERANGE;
+    value = int_max;
+    goto finish;
+    finish:
+    // If no conversion is performed we return the value of 0 and *endptr
+    // is set to the nptr.
+    bool conv_performed = (digits_read > 0);
+    if(!conv_performed) {
         value = 0;
-        goto end;
     }
-    if(value == max_modulo) {
-        if(coef == 1) {
-            errno = ERANGE;
-            value = 0;
-            goto end;
+    if(endptr != NULL) {
+        if(!conv_performed) {
+            *endptr = (char *)nptr;
         }
         else {
-            value = LONG_MIN;
-            coef = 1;
+            *endptr = (char *)str;
         }
     }
-end:
-    if(endptr != NULL) {
-        *endptr = (char *)nptr;
+    *coefptr = coef;
+    return value;
+}
+
+static double strtod_generic(const char *restrict nptr, char **restrict endptr) {
+    const char *restrict str = nptr;
+    bool conv_performed = false;
+    double value = 0.0;
+    double coef = 1.0;
+    // Skip space on the beginning
+    while(isspace(*str)) {
+        ++str;
     }
-    return coef*(long)value;
+    // Check for inf and nan
+    if(strprefix_i(str, "INF")) {
+        str += sizeof "INF"-1;
+        value = HUGE_VAL;
+        conv_performed = true;
+        goto finish;
+    }
+    if(strprefix_i(str, "INFINITY")) {
+        str += sizeof "INFINITY"-1;
+        value = HUGE_VAL;
+        conv_performed = true;
+        goto finish;
+    }
+    if(strprefix_i(str, "NAN")) {
+        str += sizeof "NAN"-1;
+        value = NAN;
+        conv_performed = true;
+        if(*str == '(') {
+            while(*str != ')') {
+                ++str;
+            }
+            ++str;
+        }
+        goto finish;
+    }
+    // Parse C float
+    if(*str == '+') {
+        ++str;
+    }
+    else if(*str == '-') {
+        coef = -1.;
+        ++str;
+    }
+    int base = 10;
+    if(strprefix_i(str, "0X")) {
+        str += sizeof "0X"-1;
+        base = 16;
+    }
+    // Parse the whole part
+    while(isbase(*str, base)) {
+        long digit = todigit(*str);
+        value = 10.0*value + (double)digit;
+        ++str;
+    }
+    if(*str != '.') {
+        value = 0.0;
+        goto finish;
+    }
+    ++str;
+    // Parse the fractional part
+    long exp = 1;
+    while(isbase(*str, base)) {
+        long digit = todigit(*str);
+        double fract = (double)digit;
+        long cexp = exp;
+        while(cexp-- != 0) {
+            fract /= (double)base;
+        }
+        value += fract;
+        ++exp;
+        ++str;
+    }
+    // Parse the exponent
+    if((base == 10 && strprefix_i(str, "E"))
+       || (base == 16 && strprefix_i(str, "P")))
+    {
+        ++str;
+        long exp = 0;
+        long exp_coef = 1;
+        if(*str == '+') {
+            ++str;
+        }
+        else if(*str == '-') {
+            exp_coef = -1;
+            ++str;
+        }
+        while(isdigit(*str)) {
+            exp = 10*exp + (long)(*str-'0');
+            ++str;
+        }
+        if(exp_coef == 1) {
+            while(exp--!=0) value = value * base;
+        }
+        else if(exp_coef == -1) {
+            while(exp--!=0) value = value / base;
+        }
+    }
+    if(!isfinite(value)) {
+        errno = ERANGE;
+        value = coef*HUGE_VAL;
+    }
+    conv_performed = true;
+    finish:
+    if(endptr != NULL) {
+        if(conv_performed) {
+            *endptr = (char *)str;
+        }
+        else {
+            *endptr = (char *)nptr;
+        }
+    }
+    return coef*value;
 }
 
-long long
-strtoll(const char *restrict nptr, char **restrict endptr, int base) {
-    return 0;
+intl strtol(const char *restrict nptr, char **restrict endptr, int base) {
+    intull int_max = (intull)LONG_MAX;
+    intl coef;
+    intull modulo = strtoi_generic(nptr, endptr, base, &coef, int_max);
+    intl value;
+    if(modulo == int_max) {
+        value = LONG_MIN;
+    }
+    else {
+        value = coef * (intl)modulo;
+    }
+    return value;
 }
 
-unsigned long
-strtoul(const char *restrict nptr, char **restrict endptr, int base) {
-    return 0;
+intll strtoll(const char *restrict nptr, char **restrict endptr, int base) {
+    intull int_max = (intull)LLONG_MAX;
+    intl coef;
+    intull modulo = strtoi_generic(nptr, endptr, base, &coef, int_max);
+    intll value;
+    if(modulo == int_max) {
+        value = LLONG_MIN;
+    }
+    else {
+        value = (intll)coef * (intll)modulo;
+    }
+    return value;
 }
 
-unsigned long long
-strtoull(const char *restrict nptr, char **restrict endptr, int base) {
-    return 0;
+intul strtoul(const char *restrict nptr, char **restrict endptr, int base) {
+    intull int_max = (intull)ULONG_MAX;
+    intull value = strtoi_generic(nptr, endptr, base, NULL, int_max);
+    return (intul)value;
+}
+
+intull strtoull(const char *restrict nptr, char **restrict endptr, int base) {
+    intull int_max = (intull)ULLONG_MAX;
+    return strtoi_generic(nptr, endptr, base, NULL, int_max);
 }
 
 double atof(const char *nptr) {
@@ -148,13 +329,13 @@ long long int atoll(const char *nptr) {
 }
 
 double strtod(const char *restrict nptr, char **restrict endptr) {
-    return 0;
+    return strtod_generic(nptr, endptr);
 }
 
 float strtof(const char *restrict nptr, char **restrict endptr) {
-    return 0;
+    return (float)strtod_generic(nptr, endptr);
 }
 
 long double strtold(const char *restrict nptr, char **restrict endptr) {
-    return 0;
+    return (long double)strtod_generic(nptr, endptr);
 }
diff --git a/inc/errno.h b/inc/errno.h
index a1783de..50f3328 100644
--- a/inc/errno.h
+++ b/inc/errno.h
@@ -5,4 +5,4 @@
 #define ERANGE 3
 
 // TODO: make it thread-local
-int errno;
+extern int errno;
diff --git a/inc/math.h b/inc/math.h
index 98557be..1b398fa 100644
--- a/inc/math.h
+++ b/inc/math.h
@@ -21,11 +21,11 @@ typedef double double_t;
 #define FP_INFINITE  1
 #define FP_NAN       2
 
-FP_INFINITE
-FP_NAN
-FP_NORMAL
-FP_SUBNORMAL
-FP_ZERO
+//FP_INFINITE
+//FP_NAN
+//FP_NORMAL
+//FP_SUBNORMAL
+//FP_ZERO
 #define FP_FAST_FMA  1
 #define FP_FAST_FMAF 1
 #define FP_FAST_FMAL 1
@@ -39,8 +39,11 @@ FP_ZERO
 
 // TODO: implement this
 #define fpclassify(x) 0
-#define isfinite(x)   0
-#define isinf(x)      0
+
+// HACK: If its fine just remove the comment
+#define isfinite(x)   ((double)(x) != HUGE_VAL && (double)(x) != -HUGE_VAL)
+#define isinf(x)      (!(isinf(x)))
+
 #define isnan(x)      0
 #define isnormal(x)   0
 #define signbit(x)    0
diff --git a/inc/stdlib.h b/inc/stdlib.h
index 97d960d..19aad8f 100644
--- a/inc/stdlib.h
+++ b/inc/stdlib.h
@@ -1,4 +1,3 @@
-
 #pragma once
 
 #if !defined(NULL)
@@ -72,7 +71,7 @@ void *realloc(void *ptr, size_t size);
 
 // #ifdef __STDC_WANT_LIB_EXT1__
 // 	typedef void (*constraint_handler_t)(const char * restrict msg, void * restrict ptr, errno_t error);
-	
+
 // 	constraint_handler_t set_constraint_handler_s(constraint_handler_t handler);
 // 	void abort_handler_s(const char * restrict msg, void * restrict ptr, errno_t error);
 // 	void ignore_handler_s(const char * restrict msg, void * restrict ptr, errno_t error);
diff --git a/test/test.c b/test/test.c
index 9ca0053..41f6d19 100644
--- a/test/test.c
+++ b/test/test.c
@@ -1,6 +1,8 @@
 #include <assert.h>
 #include <ctype.h>
 #include <stdio.h>
+#include <stdlib.h>
+#include <errno.h>
 
 int main(int argc, char** argv) {
     for (int i = 0; i < argc; i++) {
@@ -13,5 +15,24 @@ int main(int argc, char** argv) {
     for (char c = 'a'; c != 'z'; ++c) {
         assert(isupper(toupper(c)));
     }
-    return 0;
-}
+
+    double v0 = strtod("0X1.BC70A3D70A3D7P+6", NULL);
+
+    // parsing with error handling
+    const char *p = "111.11 -2.22 Nan nan(2) inF 0X1.BC70A3D70A3D7P+6  1.18973e+4932zzz";
+
+    char *end;
+    for (double f = strtod(p, &end); p != end; f = strtod(p, &end)) {
+        printf("'%.*s' -> ", (int)(end - p), p);
+        p = end;
+        if (errno == ERANGE){
+            printf("range error, got ");
+        }
+
+        printf("%f\n", f);
+    }
+
+    // parsing without error handling
+    double v1 = strtod("  -0.0000000123junk", NULL);
+    double v2 = strtod("junk", NULL);
+}
\ No newline at end of file