From 2b83b2c9993319e242389505cc899ceacdea58c5 Mon Sep 17 00:00:00 2001 From: fvogel Date: Wed, 2 Sep 2020 21:04:25 +0000 Subject: Implementation of TIP #585 - Promote the INDEX_TEMP_TABLE flag of Tcl_GetIndexFromObj*() to the public interface --- doc/GetIndex.3 | 19 +++++++++++++------ generic/tcl.h | 9 ++++++--- generic/tclFCmd.c | 4 ++-- generic/tclIndexObj.c | 8 ++++---- generic/tclInt.h | 9 --------- generic/tclTestObj.c | 2 +- 6 files changed, 26 insertions(+), 25 deletions(-) diff --git a/doc/GetIndex.3 b/doc/GetIndex.3 index 17a31d4..8591c56 100644 --- a/doc/GetIndex.3 +++ b/doc/GetIndex.3 @@ -27,19 +27,22 @@ Interpreter to use for error reporting; if NULL, then no message is provided on errors. .AP Tcl_Obj *objPtr in/out The string value of this value is used to search through \fItablePtr\fR. -The internal representation is modified to hold the index of the matching +If the \fBTCL_INDEX_TEMP_TABLE\fR flag is not specified, +the internal representation is modified to hold the index of the matching table entry. .AP "const char *const" *tablePtr in An array of null-terminated strings. The end of the array is marked by a NULL string pointer. -Note that references to the \fItablePtr\fR may be retained in the +Note that, unless the \fBTCL_INDEX_TEMP_TABLE\fR flag is specified, +references to the \fItablePtr\fR may be retained in the internal representation of \fIobjPtr\fR, so this should represent the address of a statically-allocated array. .AP "const void" *structTablePtr in An array of arbitrary type, typically some \fBstruct\fR type. The first member of the structure must be a null-terminated string. The size of the structure is given by \fIoffset\fR. -Note that references to the \fIstructTablePtr\fR may be retained in the +Note that, unless the \fBTCL_INDEX_TEMP_TABLE\fR flag is specified, +references to the \fIstructTablePtr\fR may be retained in the internal representation of \fIobjPtr\fR, so this should represent the address of a statically-allocated array of structures. .AP int offset in @@ -50,7 +53,8 @@ Null-terminated string describing what is being looked up, such as \fBoption\fR. This string is included in error messages. .AP int flags in OR-ed combination of bits providing additional information for -operation. The only bit that is currently defined is \fBTCL_EXACT\fR. +operation. The only bits that are currently defined are \fBTCL_EXACT\fR +and \fBTCL_INDEX_TEMP_TABLE\fR. .AP int *indexPtr out The index of the string in \fItablePtr\fR that matches the value of \fIobjPtr\fR is returned here. @@ -76,7 +80,8 @@ error message to indicate what was being looked up. For example, if \fImsg\fR is \fBoption\fR the error message will have a form like .QW "\fBbad option \N'34'firt\N'34': must be first, second, or third\fR" . .PP -If \fBTcl_GetIndexFromObj\fR completes successfully it modifies the +If the \fBTCL_INDEX_TEMP_TABLE\fR was not specified, when +\fBTcl_GetIndexFromObj\fR completes successfully it modifies the internal representation of \fIobjPtr\fR to hold the address of the table and the index of the matching entry. If \fBTcl_GetIndexFromObj\fR is invoked again with the same \fIobjPtr\fR and \fItablePtr\fR @@ -84,7 +89,9 @@ arguments (e.g. during a reinvocation of a Tcl command), it returns the matching index immediately without having to redo the lookup operation. Note: \fBTcl_GetIndexFromObj\fR assumes that the entries in \fItablePtr\fR are static: they must not change between -invocations. If the value of \fIobjPtr\fR is the empty string, +invocations. This caching mechanism can be disallowed by specifying +the \fBTCL_INDEX_TEMP_TABLE\fR flag. +If the value of \fIobjPtr\fR is the empty string, \fBTcl_GetIndexFromObj\fR will treat it as a non-matching value and return \fBTCL_ERROR\fR. .PP diff --git a/generic/tcl.h b/generic/tcl.h index 02ef01e..65169c0 100644 --- a/generic/tcl.h +++ b/generic/tcl.h @@ -973,11 +973,14 @@ typedef struct Tcl_DString { #define TCL_DONT_QUOTE_HASH 8 /* - * Flag that may be passed to Tcl_GetIndexFromObj to force it to disallow - * abbreviated strings. + * Flags that may be passed to Tcl_GetIndexFromObj. + * TCL_EXACT disallows abbreviated strings. + * TCL_INDEX_TEMP_TABLE disallows caching of lookups. A possible use case is + * a table that will not live long enough to make it worthwhile. */ -#define TCL_EXACT 1 +#define TCL_EXACT 1 +#define TCL_INDEX_TEMP_TABLE 2 /* *---------------------------------------------------------------------------- diff --git a/generic/tclFCmd.c b/generic/tclFCmd.c index 3babd43..d6a152a 100644 --- a/generic/tclFCmd.c +++ b/generic/tclFCmd.c @@ -1085,7 +1085,7 @@ TclFileAttrsCmd( } if (Tcl_GetIndexFromObj(interp, objv[0], attributeStrings, - "option", INDEX_TEMP_TABLE, &index) != TCL_OK) { + "option", TCL_INDEX_TEMP_TABLE, &index) != TCL_OK) { goto end; } if (Tcl_FSFileAttrsGet(interp, index, filePtr, @@ -1110,7 +1110,7 @@ TclFileAttrsCmd( for (i = 0; i < objc ; i += 2) { if (Tcl_GetIndexFromObj(interp, objv[i], attributeStrings, - "option", INDEX_TEMP_TABLE, &index) != TCL_OK) { + "option", TCL_INDEX_TEMP_TABLE, &index) != TCL_OK) { goto end; } if (i + 1 == objc) { diff --git a/generic/tclIndexObj.c b/generic/tclIndexObj.c index 4749e6e..a0a31da 100644 --- a/generic/tclIndexObj.c +++ b/generic/tclIndexObj.c @@ -114,7 +114,7 @@ Tcl_GetIndexFromObj( int flags, /* 0 or TCL_EXACT */ int *indexPtr) /* Place to store resulting integer index. */ { - if (!(flags & INDEX_TEMP_TABLE)) { + if (!(flags & TCL_INDEX_TEMP_TABLE)) { /* * See if there is a valid cached result from a previous lookup (doing the @@ -216,7 +216,7 @@ GetIndexFromObjList( tablePtr[objc] = NULL; result = Tcl_GetIndexFromObjStruct(interp, objPtr, tablePtr, - sizeof(char *), msg, flags | INDEX_TEMP_TABLE, indexPtr); + sizeof(char *), msg, flags | TCL_INDEX_TEMP_TABLE, indexPtr); ckfree(tablePtr); @@ -280,7 +280,7 @@ Tcl_GetIndexFromObjStruct( * See if there is a valid cached result from a previous lookup. */ - if (!(flags & INDEX_TEMP_TABLE)) { + if (!(flags & TCL_INDEX_TEMP_TABLE)) { irPtr = TclFetchIntRep(objPtr, &indexType); if (irPtr) { indexRep = (IndexRep *)irPtr->twoPtrValue.ptr1; @@ -344,7 +344,7 @@ Tcl_GetIndexFromObjStruct( * operation. */ - if (!(flags & INDEX_TEMP_TABLE)) { + if (!(flags & TCL_INDEX_TEMP_TABLE)) { irPtr = TclFetchIntRep(objPtr, &indexType); if (irPtr) { indexRep = (IndexRep *)irPtr->twoPtrValue.ptr1; diff --git a/generic/tclInt.h b/generic/tclInt.h index 2f12b8f..7791a1c 100644 --- a/generic/tclInt.h +++ b/generic/tclInt.h @@ -2606,15 +2606,6 @@ typedef struct TclFileAttrProcs { } TclFileAttrProcs; /* - * Private flag value which controls Tcl_GetIndexFromObj*() routines - * to instruct them not to cache lookups because the table will not - * live long enough to make it worthwhile. Must not clash with public - * flag value TCL_EXACT. - */ - -#define INDEX_TEMP_TABLE 2 - -/* * Opaque handle used in pipeline routines to encapsulate platform-dependent * state. */ diff --git a/generic/tclTestObj.c b/generic/tclTestObj.c index 99cb1f4..bd5d92e 100644 --- a/generic/tclTestObj.c +++ b/generic/tclTestObj.c @@ -627,7 +627,7 @@ TestindexobjCmd( argv[objc-4] = NULL; result = Tcl_GetIndexFromObj((setError? interp : NULL), objv[3], - argv, "token", INDEX_TEMP_TABLE|(allowAbbrev? 0 : TCL_EXACT), + argv, "token", TCL_INDEX_TEMP_TABLE|(allowAbbrev? 0 : TCL_EXACT), &index); ckfree(argv); if (result == TCL_OK) { -- cgit v0.12