sim: switch working directory

If this option is enabled, the working path of nuttx will be modified to the folder where the nuttx file is located.

Signed-off-by: yinshengkai <yinshengkai@xiaomi.com>

arch/sim/Kconfig

@@ -159,6 +159,17 @@ config SIM_HOSTFS
 	---help---
 		Access host filesystem through HostFS.
 
+config SIM_IMAGEPATH_AS_CWD
+	bool "Simulator switch working directory"
+	default n
+	---help---
+		If this option is enabled, the working path of nuttx will be modified
+		to the folder where the nuttx file is located.
+		It affects the file access of hostfs, which will start looking for
+		files based on the nuttx image folder.
+		Otherwise the default $CWD will be used as the starting path for the search.
+		Absolute paths are never affected.
+
 choice
 	prompt "Simulated Network Interface"
 	default SIM_NETDEV

arch/sim/src/nuttx-names.in

@@ -39,6 +39,7 @@ NXSYMBOLS(backtrace)
 NXSYMBOLS(bind)
 NXSYMBOLS(calloc)
 NXSYMBOLS(chmod)
+NXSYMBOLS(chdir)
 NXSYMBOLS(chown)
 NXSYMBOLS(clock_gettime)
 NXSYMBOLS(close)
@@ -106,6 +107,7 @@ NXSYMBOLS(pthread_sigmask)
 NXSYMBOLS(puts)
 NXSYMBOLS(read)
 NXSYMBOLS(readdir)
+NXSYMBOLS(readlink)
 NXSYMBOLS(readv)
 NXSYMBOLS(realloc)
 NXSYMBOLS(recvfrom)

arch/sim/src/sim/posix/sim_hostmisc.c

@@ -22,10 +22,19 @@
  * Included Files
  ****************************************************************************/
 
+#include <limits.h>
+#include <stdio.h>
 #include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
 
 #include "sim_internal.h"
 
+#ifdef CONFIG_HOST_MACOS
+#include <sys/syslimits.h>
+#include <mach-o/dyld.h>
+#endif
+
 /****************************************************************************
  * Public Function Prototypes
  ****************************************************************************/
@@ -88,3 +97,38 @@ int host_backtrace(void** array, int size)
   return backtrace(array, size);
 #endif
 }
+
+/****************************************************************************
+ * Name: host_init_cwd
+ ****************************************************************************/
+
+#ifdef CONFIG_SIM_IMAGEPATH_AS_CWD
+void host_init_cwd(void)
+{
+  char *name;
+  char path[PATH_MAX];
+  int len = PATH_MAX;
+
+  /* Get the absolute path of the executable file */
+
+#  ifdef CONFIG_HOST_LINUX
+  len = readlink("/proc/self/exe", path, len);
+  if (len < 0)
+    {
+      perror("readlink  failed");
+      return;
+    }
+#  else
+  if (_NSGetExecutablePath(path, &len) < 0)
+    {
+      perror("_NSGetExecutablePath failed");
+      return;
+    }
+#  endif
+
+  path[len] = '\0';
+  name = strrchr(path, '/');
+  *++name = '\0';
+  chdir(path);
+}
+#endif

arch/sim/src/sim/sim_initialize.c

@@ -254,6 +254,10 @@ static int sim_loop_task(int argc, char **argv)
 
 void up_initialize(void)
 {
+#ifdef CONFIG_SIM_IMAGEPATH_AS_CWD
+  host_init_cwd();
+#endif
+
 #ifdef CONFIG_PM
   /* Initialize the power management subsystem.  This MCU-specific function
    * must be called *very* early in the initialization sequence *before* any

arch/sim/src/sim/sim_internal.h

@@ -164,6 +164,10 @@ void *sim_doirq(int irq, void *regs);
 void host_abort(int status);
 int  host_backtrace(void** array, int size);
 
+#ifdef CONFIG_SIM_IMAGEPATH_AS_CWD
+void host_init_cwd(void);
+#endif
+
 /* sim_hostmemory.c *********************************************************/
 
 void *host_allocheap(size_t sz);

arch/sim/src/sim/win/sim_hostmisc.c

@@ -22,7 +22,15 @@
  * Included Files
  ****************************************************************************/
 
+#include <direct.h>
+#include <stdio.h>
+#include <string.h>
+
+#include <io.h>
 #include <windows.h>
+#include <libloaderapi.h>
+
+#include "sim_internal.h"
 
 /****************************************************************************
  * Public Functions
@@ -47,3 +55,32 @@ int host_backtrace(void** array, int size)
 {
   return CaptureStackBackTrace(0, size, array, NULL);
 }
+
+/****************************************************************************
+ * Name: host_init_cwd
+ ****************************************************************************/
+
+#ifdef CONFIG_SIM_IMAGEPATH_AS_CWD
+void host_init_cwd(void)
+{
+  char *name;
+  char path[MAX_PATH];
+
+  /* Get the absolute path of the executable file */
+
+  if (GetModuleFileNameA(GetModuleHandleA(NULL), path, MAX_PATH) == 0)
+    {
+      perror("GetModuleFileNameA failed");
+      return;
+    }
+
+  name = strrchr(path, '/');
+  if (name == NULL)
+    {
+      name = strrchr(path, '\\');
+    }
+
+  *++name = '\0';
+  _chdir(path);
+}
+#endif