SUBR_TAG.patch

   1 Subject: new variable type 'subroutine', as pointer to functions
   2
   3 You can get the variable holding a pointer to a function simpley by assignment:
   4
   5   my_t_print = t_print
   6
   7 and use this like a normal function name:
   8
   9   my_t_print("hello world\n")
  10
  11 or with the call() macro:
  12
  13   call(my_t_print, "hello world\n")
  14
  15 The define() macro returns also a pointer to the just created function:
  16
  17   my_t_print = define("bla", 't_print(=$args)' "\n")
  18   my_t_print("hello world\n")
  19
  20 ---
  21
  22  source/interpret.c |   31 ++++++++++++++++++++++++++++++-
  23  source/interpret.h |    3 ++-
  24  source/macro.c     |   25 ++++++++++++++++++-------
  25  3 files changed, 50 insertions(+), 9 deletions(-)
  26
  27 diff --quilt old/source/interpret.c new/source/interpret.c
  28 --- old/source/interpret.c
  29 +++ new/source/interpret.c
  30 @@ -344,6 +344,7 @@ int AddSym(Symbol *sym, char **msg)
  31         *msg = "macro too large";
  32         return 0;
  33      }
  34 +    sym->added = 1;
  35      ProgP->sym = sym;
  36      ProgP++;
  37      return 1;
  38 @@ -838,6 +839,7 @@ Symbol *InstallSymbol(const char *name,
  39      strcpy(s->name, name);
  40      s->type = type;
  41      s->value = value;
  42 +    s->added = 0;
  43      if (type == LOCAL_SYM) {
  44         s->next = LocalSymList;
  45         LocalSymList = s;
  46 @@ -862,7 +864,7 @@ Symbol *PromoteToGlobal(Symbol *sym)
  47  {
  48      Symbol *s;
  49
  50 -    if (sym->type != LOCAL_SYM)
  51 +    if (sym->type != LOCAL_SYM || sym->added)
  52         return sym;
  53
  54      /* Remove sym from the local symbol list */
  55 @@ -1419,6 +1421,11 @@ static int pushSymVal(void)
  56                 &symVal, &errMsg)) {
  57             return execError(errMsg, s->name);
  58          }
  59 +    } else if (s->type == C_FUNCTION_SYM
  60 +            || s->type == MACRO_FUNCTION_SYM
  61 +            || s->type == ACTION_ROUTINE_SYM) {
  62 +        symVal.tag = SUBR_TAG;
  63 +        symVal.val.sym = s;
  64      } else
  65         return execError("reading non-variable: %s", s->name);
  66      if (symVal.tag == NO_TAG && !inTypeOfMode) {
  67 @@ -2517,12 +2524,26 @@ static int callSubroutineFromSymbol(Symb
  68      Program *prog;
  69      char *errMsg;
  70      int haveNamedArgs = (nArgs < 0);
  71 +    DataValue *symValPtr = NULL;
  72
  73      if (haveNamedArgs) {
  74          nArgs = -nArgs - 1;
  75          POP(argArray);
  76      }
  77
  78 +    if (sym->type == LOCAL_SYM) {
  79 +        symValPtr = &FP_GET_SYM_VAL(FrameP, sym);
  80 +    } else if (sym->type == GLOBAL_SYM) {
  81 +        symValPtr = &sym->value;
  82 +    }
  83 +    if (symValPtr) {
  84 +        if (symValPtr->tag == SUBR_TAG) {
  85 +            sym = symValPtr->val.sym;
  86 +        } else {
  87 +            return execError("%s is not a variable holding a subroutine pointer", sym->name);
  88 +        }
  89 +    }
  90 +
  91      /*
  92      ** If the subroutine is built-in, call the built-in routine
  93      */
  94 @@ -3891,6 +3912,9 @@ static int typeOfOut(void)
  95          case ARRAY_TAG:
  96              retVal.val.str.rep = PERM_ALLOC_STR("ARRAY");
  97              break;
  98 +        case SUBR_TAG:
  99 +            retVal.val.str.rep = PERM_ALLOC_STR("SUBROUTINE");
 100 +            break;
 101      }
 102      retVal.val.str.len = strlen(retVal.val.str.rep);
 103
 104 @@ -4152,6 +4176,8 @@ static const char *tagToStr(enum typeTag
 105              return "string";
 106          case ARRAY_TAG:
 107              return "array";
 108 +        case SUBR_TAG:
 109 +            return "subroutine";
 110          case NO_TAG:
 111          default:
 112              return "no value";
 113 @@ -4278,6 +4304,9 @@ static void dumpVal(DataValue dv)
 114              printd("<%s %u:%8p>", tagToStr(ARRAY_TAG), ArraySize(&dv),
 115                      dv.val.arrayPtr);
 116              break;
 117 +        case SUBR_TAG:
 118 +            printd("<%s %s>", tagToStr(SUBR_TAG), dv.val.sym->name);
 119 +            break;
 120          case NO_TAG:
 121              if (!dv.val.inst) {
 122                  printd("<%s>", tagToStr(NO_TAG));
 123 diff --quilt old/source/interpret.h new/source/interpret.h
 124 --- old/source/interpret.h
 125 +++ new/source/interpret.h
 126 @@ -50,7 +50,7 @@ enum operations {
 127      N_OPS
 128  };
 129
 130 -enum typeTags {NO_TAG, INT_TAG, STRING_TAG, ARRAY_TAG};
 131 +enum typeTags {NO_TAG, INT_TAG, STRING_TAG, ARRAY_TAG, SUBR_TAG};
 132
 133  enum execReturnCodes {MACRO_TIME_LIMIT, MACRO_PREEMPT, MACRO_DONE, MACRO_ERROR};
 134
 135 @@ -102,6 +102,7 @@ typedef struct SymbolRec {
 136      enum symTypes type;
 137      DataValue value;
 138      struct SymbolRec *next;     /* to link to another */
 139 +    int added;
 140  } Symbol;
 141
 142  typedef struct ProgramTag {
 143 diff --quilt old/source/macro.c new/source/macro.c
 144 --- old/source/macro.c
 145 +++ new/source/macro.c
 146 @@ -3805,27 +3805,35 @@ static int filenameDialogMS(WindowInfo*
 147  static int callMS(WindowInfo *window, DataValue *argList,
 148          int nArgs, DataValue *result, char **errMsg)
 149  {
 150 -    char stringStorage[TYPE_INT_STR_SIZE(int)];
 151      Symbol *sym;
 152 -    char *fnname;
 153
 154      if (nArgs < 1) {
 155          *errMsg = "subroutine %s called without arguments";
 156          return False;
 157      }
 158 -    if (!readStringArg(argList[0], &fnname, stringStorage, errMsg)) {
 159 -        return False;
 160 +    if (argList[0].tag == SUBR_TAG) {
 161 +        sym = argList[0].val.sym;
 162 +    } else {
 163 +        char stringStorage[TYPE_INT_STR_SIZE(int)];
 164 +        char *fnname;
 165 +
 166 +        if (!readStringArg(argList[0], &fnname, stringStorage, errMsg)) {
 167 +            return False;
 168 +        }
 169 +
 170 +        sym = LookupSymbol(fnname);
 171      }
 172 -    sym = LookupSymbol(fnname);
 173 +
 174      if (!sym) {
 175          *errMsg = "subroutine name invalid";
 176          return False;
 177      }
 178 +
 179      return OverlayRoutineFromSymbol(sym, nArgs, 1);
 180  }
 181
 182  /*
 183 - * define(func_name, func_body[, "override"])
 184 + * subr = define(func_name, func_body[, "override"])
 185   */
 186  static int defineMS(WindowInfo *window, DataValue *argList, int nArgs,
 187          DataValue *result, char **errMsg)
 188 @@ -3839,7 +3847,6 @@ static int defineMS(WindowInfo *window,
 189      char *override = NULL;
 190      Program *prog;
 191      Symbol *sym;
 192 -    DataValue subrPtr;
 193
 194      if (nArgs < 2 || nArgs > 3) {
 195          return wrongNArgsErr(errMsg);
 196 @@ -3909,11 +3916,15 @@ static int defineMS(WindowInfo *window,
 197              sym->value.val.prog = prog;
 198          }
 199      } else {
 200 +        DataValue subrPtr;
 201          subrPtr.tag = NO_TAG;
 202          subrPtr.val.prog = prog;
 203          sym = InstallSymbol(name, MACRO_FUNCTION_SYM, subrPtr);
 204      }
 205
 206 +    result->tag = SUBR_TAG;
 207 +    result->val.sym = sym;
 208 +
 209      return True;
 210  }
 211