first commit

user/ulib.c

@@ -0,0 +1,147 @@
+#include "kernel/types.h"
+#include "kernel/stat.h"
+#include "kernel/fcntl.h"
+#include "user/user.h"
+
+//
+// wrapper so that it's OK if main() does not call exit().
+//
+void
+_main()
+{
+  extern int main();
+  main();
+  exit(0);
+}
+
+char*
+strcpy(char *s, const char *t)
+{
+  char *os;
+
+  os = s;
+  while((*s++ = *t++) != 0)
+    ;
+  return os;
+}
+
+int
+strcmp(const char *p, const char *q)
+{
+  while(*p && *p == *q)
+    p++, q++;
+  return (uchar)*p - (uchar)*q;
+}
+
+uint
+strlen(const char *s)
+{
+  int n;
+
+  for(n = 0; s[n]; n++)
+    ;
+  return n;
+}
+
+void*
+memset(void *dst, int c, uint n)
+{
+  char *cdst = (char *) dst;
+  int i;
+  for(i = 0; i < n; i++){
+    cdst[i] = c;
+  }
+  return dst;
+}
+
+char*
+strchr(const char *s, char c)
+{
+  for(; *s; s++)
+    if(*s == c)
+      return (char*)s;
+  return 0;
+}
+
+char*
+gets(char *buf, int max)
+{
+  int i, cc;
+  char c;
+
+  for(i=0; i+1 < max; ){
+    cc = read(0, &c, 1);
+    if(cc < 1)
+      break;
+    buf[i++] = c;
+    if(c == '\n' || c == '\r')
+      break;
+  }
+  buf[i] = '\0';
+  return buf;
+}
+
+int
+stat(const char *n, struct stat *st)
+{
+  int fd;
+  int r;
+
+  fd = open(n, O_RDONLY);
+  if(fd < 0)
+    return -1;
+  r = fstat(fd, st);
+  close(fd);
+  return r;
+}
+
+int
+atoi(const char *s)
+{
+  int n;
+
+  n = 0;
+  while('0' <= *s && *s <= '9')
+    n = n*10 + *s++ - '0';
+  return n;
+}
+
+void*
+memmove(void *vdst, const void *vsrc, int n)
+{
+  char *dst;
+  const char *src;
+
+  dst = vdst;
+  src = vsrc;
+  if (src > dst) {
+    while(n-- > 0)
+      *dst++ = *src++;
+  } else {
+    dst += n;
+    src += n;
+    while(n-- > 0)
+      *--dst = *--src;
+  }
+  return vdst;
+}
+
+int
+memcmp(const void *s1, const void *s2, uint n)
+{
+  const char *p1 = s1, *p2 = s2;
+  while (n-- > 0) {
+    if (*p1 != *p2) {
+      return *p1 - *p2;
+    }
+    p1++;
+    p2++;
+  }
+  return 0;
+}
+
+void *
+memcpy(void *dst, const void *src, uint n)
+{
+  return memmove(dst, src, n);
+}