Restructure project, add gebs_exists() and gebs_mkdir()

.gitignore

@@ -0,0 +1,2 @@
+build
+gebs

example/.gitignore

@@ -1,3 +0,0 @@
-gebs
-a.out
-main

example/main.c

@@ -1,7 +0,0 @@
-#include <stdio.h>
-
-int main(void)
-{
-    printf("Hello world\n");
-    return 0;
-}

example/self_rebuild.c

@@ -0,0 +1,11 @@
+#include <stdio.h>
+#define GEBS_IMPLEMENTATION
+#include "../gebs.h"
+
+int main(int argc, char ** argv)
+{
+    gebs_rebuild_self(argc, argv, "cc", "-o", "self_rebuild", __FILE__);
+
+    printf("Hello world\n");
+    return 0;
+}

gebs.c

@@ -1,13 +1,16 @@
 #define GEBS_IMPLEMENTATION
-#include "../gebs.h"
+#include "gebs.h"
 
 int main(int argc, char ** argv)
 {
     gebs_rebuild_self(argc, argv, "cc", "-o", "gebs", __FILE__);
 
-    if (GEBS_CMD("gcc", "-o", "main", "main.c") != 0) {
-        return 1;
+    if (!gebs_exists("build")) {
+        gebs_mkdir("build");
     }
-    
+
+    if (GEBS_CMD("gcc", "-o", "build/self_rebuild", "example/self_rebuild.c") != 0)
+        return 1;
+
     return 0;
 }

gebs.h

@@ -164,6 +164,8 @@ typedef struct {
 
 bool gebs_rename(const char *a, const char *b);
 bool gebs_remove(const char *p);
+bool gebs_mkdir(const char *p);
+bool gebs_exists(const char *p);
 
 // ----------------------------------------------------------------------------
 // Commands
@@ -216,6 +218,10 @@ void gebs_rebuild_self1_alloc(Gebs_Allocator *alloc, int argc, char ** argv,
 
 int gebs_cmd_run_sync_alloc(Gebs_Allocator *alloc, Gebs_Cmd *cmd)
 {
+    Gebs_String_Builder sb = {0};
+    gebs_nsl_join_alloc(alloc, cmd, &sb, " ");
+    GEBS_LOGI("cmd `%s`\n", sb.items);
+
 #if GEBS_PLATFORM == GEBS_PLATFORM_POSIX
     // Clone the list
     Gebs_Cmd new_cmd = {0};
@@ -287,6 +293,25 @@ void *gebs_default_allocator_realloc(void *memory, size_t prev_size, size_t new_
 // Filesystem operations
 // ----------------------------------------------------------------------------
 
+bool gebs_mkdir(const char *p)
+{
+#if GEBS_PLATFORM == GEBS_PLATFORM_POSIX
+    return mkdir(p, 0777) == 0;
+#else
+#   error "gebs_mkdir unknown platform"
+#endif
+}
+
+bool gebs_exists(const char *p)
+{
+#if GEBS_PLATFORM == GEBS_PLATFORM_POSIX
+    struct stat st;
+    return stat(p, &st) == 0;
+#else
+#   error "gebs_exists unknown platform"
+#endif
+}
+
 bool gebs_rename(const char *a, const char *b)
 {
     GEBS_LOGO("rename %s -> %s\n", a, b);