libc: Add (f)getc, getchar, and fgets

libc/include/stdio.h

@@ -81,6 +81,18 @@ extern "C"
     /* Write a string to stream. */
     int fputs(const char* str, FILE* stream);
 
+    /* Read a character from stream. */
+    int fgetc(FILE* stream);
+
+    /* Read a character from stream. */
+    int getc(FILE* stream);
+
+    /* Read a character from standard input. */
+    int getchar();
+
+    /* Read a line from stream. */
+    char* fgets(char* buf, size_t size, FILE* stream);
+
     /* Clear the error and end-of-file indicators in stream. */
     void clearerr(FILE* stream);
 

libc/src/stdio.cpp

@@ -187,6 +187,42 @@ extern "C"
         return (rc < 0) ? -1 : 0;
     }
 
+    int fgetc(FILE* stream)
+    {
+        u8 value;
+        ssize_t rc = read(stream->_fd, &value, 1);
+        if (rc <= 0) return EOF;
+        return value;
+    }
+
+    int getc(FILE* stream)
+    {
+        return fgetc(stream);
+    }
+
+    int getchar()
+    {
+        return fgetc(stdin);
+    }
+
+    char* fgets(char* buf, size_t size, FILE* stream)
+    {
+        size_t i = 0;
+        while (i + 1 < size)
+        {
+            int c = fgetc(stream);
+            if (c == EOF) break;
+            buf[i++] = (char)c;
+            if (c == '\n') break;
+        }
+
+        if (i == 0) return NULL;
+
+        buf[i] = 0;
+
+        return buf;
+    }
+
     void clearerr(FILE* stream)
     {
         stream->_eof = stream->_err = 0;