Changeset 849 for Whitix/trunk/fs/vfs/load.c

Timestamp:

08/20/08 17:55:19 (4 years ago)

Author:

mwhitworth

Message:

Add support for loading scripts via #! notation.

Files:

• Whitix/trunk/fs/vfs/load.c (modified) (14 diffs)

Whitix/trunk/fs/vfs/load.c

@@ -52 +52 @@
 
 static int ExecElf(struct ExecArgs* execArgs);
+static int ExecScript(struct ExecArgs* args);
 
 /***********************************************************************
@@ -72 +73 @@
         int err;
 
-        err=DoOpenFile(file,pathName,FILE_READ,0);
+        err=DoOpenFile(file, pathName, FILE_READ, 0);
 
         if (err)
                 return err;
-
+        
         if (file->vNode->mode & VFS_ATTR_DIR)
                 return -EISDIR;
@@ -146 +147 @@
         IrqSaveFlags(flags);
 
-        /* Map in the argument pages */
+        /* Map in the argument pages. */
         VirtSetCurrent(args->process->memManager);
 
@@ -275 +276 @@
 
         if (args->argv)
-                ExecCopyStrings(args,args->argv,argCount);
-
-        ExecCopyStrings(args,&args->process->name,1);
+                ExecCopyStrings(args,args->argv, argCount);
+
+        ExecCopyStrings(args, &args->process->name, 1);
 
         return ExecSetupArgs(args);
@@ -377 +378 @@
         ExecSetupContext(&execArgs,pathName,fds,argv);
 
-        /* Open exectuable */
+        /* Open executable */
         err=ExecOpen(pathName,&execArgs.exec);
         if (err)
@@ -401 +402 @@
         err=ExecSetupFs(process, fds);
 
-        /* Keep going through all formats until we run out of formats, then return false */
-        err=ExecElf(&execArgs);
+        if (err)
+                return err;
+
+        /* Try executing it as a script first. */
+        err=ExecScript(&execArgs);
+        
+        if (err)
+                err=ExecElf(&execArgs);
 
         if (err)
@@ -420 +427 @@
          */
 
-        execArgs.thread=ThrCreateThread(process,execArgs.entryPoint,true,(DWORD)execArgs.stackP, ((void*)-1)); /* 'process' still points to the same structure */
+        execArgs.thread=ThrCreateThread(process,execArgs.entryPoint, true, (DWORD)execArgs.stackP, ((void*)-1)); /* 'process' still points to the same structure */
 
         ThrStartThread(execArgs.thread);
@@ -454 +461 @@
         int len;
 
-        /* Seperate argv and the auxillary entries table */
-        STACK_PUSH(args->stackP,0);
-
         addr=args->process->memManager->argsStart;
 
@@ -462 +466 @@
         while (argCount--)
         {
-                STACK_PUSH(args->stackP,addr);
+                STACK_PUSH(args->stackP, addr);
                 len=strlen((char*)addr)+1;
                 addr+=len;
@@ -575 +579 @@
         PUSH_AUX_ENT(args->stackP,AT_FLAGS, 0);
 
+        /* Seperate argv and the auxillary entries table */
+        STACK_PUSH(args->stackP,0);
+
         ExecSetupStack(args);
 
@@ -679 +686 @@
 }
 
+static int ExecRemoveFirstArg(struct ExecArgs* args)
+{
+        char* p;
+        DWORD currVirtPage;
+        
+        if (!args->argc)
+                return 0;
+        
+        currVirtPage=VirtAllocateTemp(args->argPages[args->stackPos >> 12]);
+        
+        p=(char*)(currVirtPage+PAGE_OFFSET(args->stackPos));
+        
+        p-=2;
+        
+        /* TODO: May have to go back to a previous page. */
+        while (*p != '\0' && p > (char*)currVirtPage)
+                p--;
+                
+        args->stackPos=(DWORD)(p-(char*)currVirtPage);
+                
+        args->argc--;
+        
+        return 0;
+}
+
+static int ExecScript(struct ExecArgs* args)
+{
+        char* buffer;
+        char* copy;
+        int err;
+        char* interpName, *interpArg;
+        struct File file;
+        
+        buffer=(char*)malloc(512);
+        if (!DoReadFile(&args->exec, (BYTE*)buffer, 512))
+        {
+                KePrint("Failed to read file %s\n", args->pathName);
+                err=-EIO;
+                goto freeBuffer;
+        }
+
+        if (buffer[0] != '#' || buffer[1] != '!')
+                return -EINVAL;
+                
+        /* Parse the #! line */
+        buffer[511]='\0';
+        
+        copy=strchr(buffer, '\n');
+        
+        if (!copy)
+                copy=&buffer[511];
+                
+        *copy='\0';
+        
+        while (copy > buffer)
+        {
+                copy--;
+                if ((*copy == ' ') || (*copy == '\t'))
+                        *copy='\0';
+                else
+                        break;
+        }
+        
+        for (copy=buffer+2; (*copy == ' ') || (*copy == '\t'); copy++);
+        
+        /* Could not find the interpreter name. */
+        if (!*copy)
+                return -EINVAL;
+        
+        /* TODO: Close the open executable? */
+                
+        interpName=copy;
+        interpArg=NULL;
+        
+        for (; *copy && (*copy != ' ') && (*copy != '\t'); copy++);
+        
+        while ((*copy == ' ') || (*copy == '\t'))
+                *copy='\0';
+                
+        if (*copy)
+                interpArg=copy;
+                
+        err=ExecOpen(interpName, &file);
+        
+        if (err)
+                goto freeBuffer;
+        
+        /* Change the executable to the interpreter. */
+        memcpy(&args->exec, &file, sizeof(struct File));
+        args->process->exec=args->exec.vNode;
+        
+        /* Remove the first argument. */
+        ExecRemoveFirstArg(args);
+        
+        /* <interp> <interp args> <script name>. Done in reverse order. */
+        
+        ExecCopyStrings(args, &args->process->name, 1);
+        
+        if (interpArg)
+                ExecCopyStrings(args, &interpArg, 1);
+        
+        ExecCopyStrings(args, &interpName, 1);
+        
+        err=ExecElf(args);
+        
+freeBuffer:             
+        free(buffer);
+        
+        return err;
+}
+
 /* TODO:
    - Improve resource cleanup
@@ -706 +824 @@
         char* interpreter=NULL;
 
+        DoSeekFile(&args->exec, 0, 0);
+
         /* Should calculate total program header size. TODO: Memory map in. See linker code. */
         buffer=(BYTE*)malloc(512);
-        if (!DoReadFile(&args->exec,buffer,512))
+        if (!DoReadFile(&args->exec, buffer, 512))
         {
                 KePrint("Failed to read file %s\n",args->pathName);
@@ -717 +837 @@
         header=(struct ElfHeader*)buffer;
 
-        if (ElfCheckHeader(header,ELF_EXEC | ELF_DYN))
-        {
-                KePrint("%s: not a valid ELF executable\n",args->pathName);
+        if (ElfCheckHeader(header, ELF_EXEC | ELF_DYN))
+        {
+                KePrint("%s: not a valid ELF executable\n", args->pathName);
                 err=-EINVAL;
                 goto freeBuffer;
@@ -821 +941 @@
         if (copiedName)
         {
-                err=Exec(pathName,fds,argv);
+                err=Exec(copiedName, fds, argv);
                 free(copiedName);
         }