libc: Add stdin

apps/init.c

@@ -24,18 +24,19 @@ int main()
 {
     if (getpid() != 1)
     {
-        printf("error: init not running as PID 1.\n");
+        fprintf(stderr, "error: init not running as PID 1.\n");
         return 1;
     }
 
     populate_devfs();
 
-    // Before this point, we don't even have an stdout and stderr. Set it up now so that child processes (and us) can
-    // print stuff.
+    // Before this point, we don't even have an stdin, stdout and stderr. Set it up now so that child processes (and us)
+    // can print stuff.
+    stdin = fopen("/dev/console", "r");
     stdout = fopen("/dev/console", "w");
     stderr = fopen("/dev/console", "w");
 
-    fprintf(stderr, "init is running as PID %d\n", getpid());
+    printf("init is running as PID %d\n", getpid());
 
     pid_t ret = fork();
 

libc/include/stdio.h

@@ -16,8 +16,10 @@ typedef struct
 
 #define EOF -1
 
+extern FILE* stdin;
 extern FILE* stdout;
 extern FILE* stderr;
+#define stdin stdin
 #define stdout stdout
 #define stderr stderr
 

libc/include/unistd.h

@@ -10,8 +10,9 @@
 #include <stdint.h>
 #include <sys/types.h>
 
-#define STDOUT_FILENO 0
-#define STDERR_FILENO 1
+#define STDIN_FILENO 0
+#define STDOUT_FILENO 1
+#define STDERR_FILENO 2
 
 #ifdef __cplusplus
 extern "C"

libc/src/init.cpp

@@ -5,6 +5,7 @@ extern "C"
 {
     void libc_init()
     {
+        stdin = fdopen(STDIN_FILENO, "r");
         stdout = fdopen(STDOUT_FILENO, "w");
         stderr = fdopen(STDERR_FILENO, "w");
     }

libc/src/stdio.cpp

@@ -8,6 +8,7 @@
 #include <sys/syscall.h>
 #include <unistd.h>
 
+FILE* stdin = nullptr;
 FILE* stderr = nullptr;
 FILE* stdout = nullptr;