rom/dos/setvar.c

   1 /*
   2     Copyright © 1995-2009, The AROS Development Team. All rights reserved.
   3     $Id$
   4
   5     Desc:
   6     Lang: English
   7 */
   8 #include <aros/debug.h>
   9
  10 #include "dos_intern.h"
  11 #include <exec/memory.h>
  12 #include <dos/dos.h>
  13 #include <dos/dosextens.h>
  14 #include <proto/exec.h>
  15 #include <proto/utility.h>
  16 #include <exec/lists.h>
  17 #include <string.h>
  18
  19 /*****************************************************************************
  20
  21     NAME */
  22 #include <dos/var.h>
  23 #include <proto/dos.h>
  24
  25         AROS_LH4(BOOL, SetVar,
  26
  27 /*  SYNOPSIS */
  28         AROS_LHA(CONST_STRPTR, name, D1),
  29         AROS_LHA(CONST_STRPTR, buffer, D2),
  30         AROS_LHA(LONG        , size, D3),
  31         AROS_LHA(LONG        , flags, D4),
  32
  33 /*  LOCATION */
  34         struct DosLibrary *, DOSBase, 150, Dos)
  35
  36 /*  FUNCTION
  37         This function will set a local or environmental variable. Although
  38         it is recommended that you only use ASCII strings within variables,
  39         this is not actually required.
  40
  41         Variable names are not case sensitive.
  42
  43         SetVar() for an already existing variable changes the variable's
  44         value to "buffer".
  45
  46     INPUTS
  47         name        -   The name of the variable to set.
  48         buffer      -   The actual data of the variable.
  49         size        -   The size of the data in the buffer.
  50         flags       -   Combination of the type of variable to set (lower
  51                         8 bits of the value), and various flags which control
  52                         this function. Flags defined are:
  53
  54                         GVF_LOCAL_ONLY  -   set a local variable only,
  55                         GVF_GLOBAL_ONLY -   set a global environmental
  56                                             variable only.
  57                         GVF_SAVE_VAR    -   If GVF_GLOBAL_ONLY is set, then
  58                                             this flag will cause SetVar() to
  59                                             save the variable to ENVARC: as well
  60                                             as to ENV:.
  61                         GVF_BINARY_VAR and GVF_DONT_NULL_TERM are stored in
  62                         the lv_Flags field for local variables, but not
  63                         used otherwise by SetVar().
  64
  65                         Note the default is to set a local environmental
  66                         variable.
  67
  68                         The following variable types are defined:
  69                         LV_VAR          - local environment variable
  70                         LV_ALIAS        - shell alias
  71                         LVF_IGNORE      - internal shell use
  72
  73                         LV_VAR and LV_ALIAS should be treated as
  74                         "exclusive or".
  75
  76
  77     RESULT
  78         Zero if this function failed, non-zero otherwise.
  79
  80     NOTES
  81         It is possible to have two variables with the same name as
  82         long as they have different types.
  83
  84     EXAMPLE
  85
  86     BUGS
  87         Only type LV_VAR can be made global.
  88
  89         If you set GVF_SAVE_VAR, and this function returns failure, the
  90         variable may have still been set in ENV:.
  91
  92     SEE ALSO
  93         DeleteVar(), FindVar(), GetVar(),
  94
  95     INTERNALS
  96         See FindVar() for a description of the inner workings of local
  97         variables.
  98
  99 *****************************************************************************/
 100 {
 101     AROS_LIBFUNC_INIT
 102
 103     /* valid input? */
 104     if(name && buffer)
 105     {
 106         /* Local variable is default. */
 107         if((flags & GVF_GLOBAL_ONLY) == 0)
 108         {
 109             ULONG nameLen = strlen(name);
 110             struct LocalVar *lv;
 111
 112             /* does a Variable with that name already exist? */
 113             if (NULL != (lv = FindVar(name, flags)))
 114             {
 115                 /* delete old value of that existing variable */
 116                 FreeMem(lv->lv_Value,lv->lv_Len);
 117             }
 118             else
 119             {
 120                 /*
 121                 ** create a LocalVar-structure and insert it into the list
 122                 */
 123                 if (NULL != (lv = AllocVec(sizeof(struct LocalVar) + nameLen + 1,
 124                                            MEMF_CLEAR|MEMF_PUBLIC) ) )
 125                 {
 126                     struct Process  *pr = (struct Process *)FindTask(NULL);
 127                     struct LocalVar *n;
 128
 129                     ASSERT_VALID_PROCESS(pr);
 130                     n = (struct LocalVar *)pr->pr_LocalVars.mlh_Head;
 131
 132                     /* init the newly created structure */
 133
 134                     lv->lv_Node.ln_Type = flags;  /* ln_Type is UBYTE! */
 135                     lv->lv_Node.ln_Name = (UBYTE *)lv + sizeof(struct LocalVar);
 136                     CopyMem(name, lv->lv_Node.ln_Name, nameLen);
 137                     lv->lv_Flags = flags & (GVF_BINARY_VAR|GVF_DONT_NULL_TERM);
 138
 139                     /*
 140                     ** First let's see whether we have to add it at the head
 141                     ** of the list as the list is still empty   OR
 142                     ** the very first element is already greater than the one
 143                     ** we want to insert
 144                     */
 145
 146                     if (n == (struct LocalVar *)&(pr->pr_LocalVars.mlh_Tail) ||
 147                         Stricmp(name, n->lv_Node.ln_Name) < 0)
 148                     {
 149                         AddHead((struct List *)&pr->pr_LocalVars,
 150                                 (struct Node *)lv);
 151                     }
 152                     else
 153                     {
 154                         /*
 155                         ** Now we can be sure that we will have to insert
 156                         ** somewhere behind the first element in the list
 157                         */
 158                         ForeachNode(&pr->pr_LocalVars, n)
 159                         {
 160                             if (Stricmp(name, n->lv_Node.ln_Name) < 0)
 161                             {
 162                                 break;
 163                             }
 164                         }
 165
 166                         if (NULL != n->lv_Node.ln_Succ)
 167                         {
 168                             Insert((struct List *)&pr->pr_LocalVars ,
 169                                    (struct Node *) lv ,
 170                                    (struct Node *) n->lv_Node.ln_Pred);
 171                         }
 172                         else
 173                         {
 174                             AddTail((struct List *)&pr->pr_LocalVars,
 175                                     (struct Node *) lv);
 176                         }
 177                     }
 178                 }
 179             }
 180
 181             /* -1 as size means: buffer contains a null-terminated string */
 182             if (-1 == size)
 183             {
 184                 /* Do NOT add 1 byte to account for the NUL char, AmigaOS(R) doesn't
 185                    do it that way. */
 186                 lv->lv_Len = strlen(buffer);
 187             }
 188             else
 189             {
 190                 lv->lv_Len = size;
 191             }
 192
 193             /* now get some memory for the value, this will implicitly set NULL if lv_Len is 0 */
 194             lv->lv_Value = AllocMem(lv->lv_Len, MEMF_PUBLIC);
 195
 196             CopyMem(buffer, lv->lv_Value, lv->lv_Len);
 197
 198             if (flags & GVF_LOCAL_ONLY)
 199                 return DOSTRUE;
 200         } /* set a local variable */
 201
 202         /* Ok, try and set a global variable. */
 203         if ((flags & GVF_LOCAL_ONLY) == 0)
 204         {
 205             BPTR file;
 206             /* as a standard: look for the file in ENV: if no path is
 207                given in the variable */
 208             UBYTE nameBuffer[384]= "ENV:";
 209
 210             AddPart(nameBuffer, name, 384);
 211
 212             /* Just try and open the file */
 213             file = Open(nameBuffer, MODE_NEWFILE);
 214
 215             if (file != BNULL)
 216             {
 217                 /* Write the data to the file */
 218                 /* size = -1 means that the value is a null-terminated
 219                    string */
 220                 if (-1 == size)
 221                 {
 222                     Write(file, buffer, strlen(buffer));
 223                 }
 224                 else
 225                 {
 226                     Write(file, buffer, size);
 227                 }
 228
 229                 Close(file);
 230             }
 231             else
 232             {
 233                 return DOSFALSE;
 234             }
 235
 236             /* Let's see whether we're supposed to make a copy of this to
 237              * envarc also...
 238              */
 239             if (0 != (flags & GVF_SAVE_VAR))
 240             {
 241                 CopyMem("ENVARC:", nameBuffer, 8);
 242                 AddPart(nameBuffer, name, 384);
 243
 244                 file = Open(nameBuffer, MODE_NEWFILE);
 245
 246                 if (file != BNULL)
 247                 {
 248                     /* Write the data to the file */
 249                     /* size = -1 means that the value is a null-terminated
 250                        string */
 251                     if (-1 == size)
 252                     {
 253                         Write(file, buffer, strlen(buffer));
 254                     }
 255                     else
 256                     {
 257                         Write(file, buffer, size);
 258                     }
 259
 260                     Close(file);
 261                 }
 262             }
 263
 264             /* We created both, bye bye */
 265             return DOSTRUE;
 266         } /* try a global variable */
 267     } /* input was valid */
 268
 269     return DOSFALSE;
 270
 271     AROS_LIBFUNC_EXIT
 272 } /* SetVar */