1 files changed, 113 insertions, 0 deletions
diff --git a/src/c/string.c b/src/c/string.c
new file mode 100644
index 0000000..5667715
--- /dev/null
+++ b/src/c/string.c
@@ -0,0 +1,113 @@
+#include"../include/types.h"
+
+size_t stringlen(char *str)
+{
+    size_t i;
+
+    for(i=0;str[i]!='\0';i++) ;
+
+    return i;
+}
+
+bool stringcmp(char *str1,char *str2)
+{
+    size_t i;
+    for(i=0;str1[i]||str2[i];i++) if(str1[i]!=str2[i]) return 0;
+    if(str1[i]==str2[i]) return 1;
+    return 0;
+}
+
+void stringcat(char *str1,char *str2)
+{
+    char *tmp=str1;
+    while(*tmp) tmp++;
+    while(*str2) *tmp++=*str2++;
+    *tmp=*str2;
+}
+
+void stringcpy(char *str1,char *str2)
+{
+    for(size_t i=0;str2[i]!='\0';i++) str1[i]=str2[i];
+}
+
+void stringrev(char *str)
+{
+    size_t i=stringlen(str)-1;
+
+    for(size_t j=0;j<i-j;j++)
+    {
+	char tmp=str[i-j];
+	str[i-j]=str[j];
+	str[j]=tmp;
+    }
+}
+
+uint32_t stoi(const char *str)
+{
+    uint32_t num=0;
+
+    for(size_t i=0;str[i]!='\0';i++)
+    {
+	if(str[i]<'0'||str[i]>'9') return num;
+	num*=10;
+	num+=str[i]-'0';
+    }
+
+    return num;
+}
+
+void itos(uint32_t num,char *str)
+{
+    if(num==0) stringcpy(str,"0");
+    else
+    {
+	size_t i=0;
+	for(;num>0;num/=10,i++) str[i]='0'+num%10;
+	str[i]='\0';
+
+	stringrev(str);
+    }
+}
+
+double stof(const char *str)
+{
+    double num=0;
+
+    bool point=0;
+    uint32_t pow=1;
+    size_t i=0;
+
+    for(;str[i]!='\0';i++)
+    {
+	if(str[i]=='.')
+	{
+	    if(point) return num/pow;
+	    point=1;
+	    continue;
+	}
+	if(str[i]<'0'||str[i]>'9') return num/pow;
+	num*=10;
+	num+=str[i]-'0';
+	if(point) pow*=10;
+    }
+
+    return num/pow;
+}
+
+const int decimals=7;
+void ftos(double num, char *str)
+{
+    itos((uint32_t)num,str);
+
+    stringcat(str,".");
+    char c[2];
+    c[1]='\0';
+
+    for(size_t i=0;i<decimals;i++)
+    {
+	num-=(uint32_t)num;
+	num*=10;
+	c[0]=(uint32_t)num+'0';
+	stringcat(str,c);
+    }
+}