usr: libc: Implement fopen() and fclose()

Signed-off-by: Ian Moffett <ian@osmora.org>

3 files changed, 122 insertions, 0 deletions

diff --git a/lib/libc/include/stdio.h b/lib/libc/include/stdio.h
index 4bbe81a..708f200 100644
--- a/lib/libc/include/stdio.h
+++ b/lib/libc/include/stdio.h
@@ -74,6 +74,8 @@ __BEGIN_DECLS
 
 size_t fread(void *__restrict ptr, size_t size, size_t n, FILE *__restrict stream);
 size_t fwrite(const void *__restrict ptr, size_t size, size_t n, FILE *__restrict stream);
+FILE *fopen(const char *__restrict path, const char *__restrict mode);
+int fclose(FILE *stream);
 
 int vsnprintf(char *s, size_t size, const char *fmt, va_list ap);
 int snprintf(char *s, size_t size, const char *fmt, ...);
diff --git a/lib/libc/src/stdio/fclose.c b/lib/libc/src/stdio/fclose.c
new file mode 100644
index 0000000..7628973
--- /dev/null
+++ b/lib/libc/src/stdio/fclose.c
@@ -0,0 +1,48 @@
+/*
+ * Copyright (c) 2023-2025 Ian Marco Moffett and the Osmora Team.
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright notice,
+ *    this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ * 3. Neither the name of Hyra nor the names of its
+ *    contributors may be used to endorse or promote products derived from
+ *    this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+ * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
+ * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+ * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+ * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#include <sys/types.h>
+#include <sys/errno.h>
+#include <stdlib.h>
+#include <stdio.h>
+#include <unistd.h>
+
+int
+fclose(FILE *stream)
+{
+    int retval;
+
+    if (stream == NULL) {
+        return -EBADF;
+    }
+
+    retval = close(stream->fd);
+    free(stream);
+    return retval;
+}
diff --git a/lib/libc/src/stdio/fopen.c b/lib/libc/src/stdio/fopen.c
new file mode 100644
index 0000000..c15dace
--- /dev/null
+++ b/lib/libc/src/stdio/fopen.c
@@ -0,0 +1,72 @@
+/*
+ * Copyright (c) 2023-2025 Ian Marco Moffett and the Osmora Team.
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright notice,
+ *    this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ * 3. Neither the name of Hyra nor the names of its
+ *    contributors may be used to endorse or promote products derived from
+ *    this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+ * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
+ * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+ * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+ * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#include <sys/types.h>
+#include <stdio.h>
+#include <string.h>
+#include <stdlib.h>
+#include <fcntl.h>
+
+FILE *
+fopen(const char *__restrict path, const char *__restrict mode)
+{
+    FILE *fhand;
+    int fd;
+    mode_t seal = 0;
+
+    if (path == NULL || mode == NULL) {
+        return NULL;
+    }
+
+    /* Create the seal from mode string */
+    if (strcmp(mode, "r") == 0) {
+        seal |= O_RDONLY;
+    } else if (strcmp(mode, "w") == 0) {
+        seal |= (O_WRONLY | O_CREAT);
+    } else if (strcmp(mode, "r+") == 0) {
+        seal |= O_RDWR;
+    } else {
+        return NULL;
+    }
+
+    /* Try to open the file descriptor */
+    fd = open(path, seal);
+    if (fd < 0) {
+        return NULL;
+    }
+
+    fhand = malloc(sizeof(*fhand));
+    if (fhand == NULL) {
+        return NULL;
+    }
+
+    fhand->fd = fd;
+    fhand->buf_mode = _IONBF;
+    return fhand;
+}