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authorsuresh <suresh>1998-06-04 13:04:41 (GMT)
committersuresh <suresh>1998-06-04 13:04:41 (GMT)
commit79184e8574c5fb83b727aaa9fb46c578a5322f49 (patch)
tree90b0bde2ea6dc78069caae969ae5dc298b9e67f2 /generic
parent565e0f9b7e15ce36dfbb22df5bb8bea63047f050 (diff)
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Changed call references of 'stat(...)' to 'TclStat(...)' & 'access(...)' to
'TclAccess(...)'. Added the "hookable" functions 'TclStat(...)', 'TclAccess(...)', & 'Tcl_OpenFileChannel(...)'. Added appropriate data structure to maintain the linked list of 'TclStat(...)', 'TclAccess(...)', & 'Tcl_OpenFileChannel(...)'. Added the appropriate "insert" and "delete" routines for each of these. A test file 'tests/iOUtil.test' has been written to test the hooking function- ality of each of the routines. 'tclInt.h' has been updated to include the function prototypes for all new functions.
Diffstat (limited to 'generic')
-rw-r--r--generic/tclIOUtil.c445
1 files changed, 444 insertions, 1 deletions
diff --git a/generic/tclIOUtil.c b/generic/tclIOUtil.c
index 7d4cff8..2f0ca63 100644
--- a/generic/tclIOUtil.c
+++ b/generic/tclIOUtil.c
@@ -18,7 +18,62 @@
#include "tclInt.h"
#include "tclPort.h"
+
+/*
+ * The following typedef declarations allow for hooking into the chain
+ * of functions maintained for 'Tcl_Stat(...)', 'Tcl_Access(...)' &
+ * 'Tcl_OpenFileChannel(...)'. Basically for each hookable function
+ * a linked list is defined.
+ */
+
+typedef struct StatProc *StatProcPtr;
+typedef struct StatProc {
+ TclStatProc_ *proc; /* Function to process a 'stat()' call */
+ StatProcPtr next; /* The next 'stat()' function to call */
+} StatProc;
+typedef struct AccessProc *AccessProcPtr;
+typedef struct AccessProc {
+ TclAccessProc_ *proc; /* Function to process a 'access()' call */
+ AccessProcPtr next; /* The next 'access()' function to call */
+} AccessProc;
+
+typedef struct OpenFileChannelProc *OpenFileChannelProcPtr;
+typedef struct OpenFileChannelProc {
+ TclOpenFileChannelProc_ *proc; /* Function to process a
+ * 'Tcl_OpenFileChannel()' call */
+ OpenFileChannelProcPtr next; /* The next 'Tcl_OpenFileChannel()'
+ * function to call */
+} OpenFileChannelProc;
+
+/*
+ * For each type of hookable function, a static node is declared to
+ * hold the function pointer for the "built-in" routine (e.g.
+ * 'TclpStat(...)') and the respective list is initialized as a pointer
+ * to that node.
+ *
+ * The "delete" functions (e.g. 'TclStatDeleteProc(...)') ensure that
+ * these statically declared nodes cannot be inadvertently removed.
+ *
+ * This method avoids the need to call any sort of "initialization"
+ * function
+ */
+
+static StatProc defaultStatProc = {
+ &TclpStat, NULL
+};
+static StatProcPtr statProcList = &defaultStatProc;
+
+static AccessProc defaultAccessProc = {
+ &TclpAccess, NULL
+};
+static AccessProcPtr accessProcList = &defaultAccessProc;
+
+static OpenFileChannelProc defaultOpenFileChannelProc = {
+ &TclpOpenFileChannel, NULL
+};
+static OpenFileChannelProcPtr openFileChannelProcList =
+ &defaultOpenFileChannelProc;
/*
*----------------------------------------------------------------------
@@ -243,7 +298,7 @@ Tcl_EvalFile(interp, fileName)
Tcl_DStringAppend(&buffer, nativeName, -1);
nativeName = Tcl_DStringValue(&buffer);
}
- if (stat(nativeName, &statBuf) == -1) {
+ if (TclStat(nativeName, &statBuf) == -1) {
Tcl_SetErrno(errno);
Tcl_AppendResult(interp, "couldn't read file \"", fileName,
"\": ", Tcl_PosixError(interp), (char *) NULL);
@@ -390,3 +445,391 @@ Tcl_PosixError(interp)
Tcl_SetErrorCode(interp, "POSIX", id, msg, (char *) NULL);
return msg;
}
+
+/*
+ *----------------------------------------------------------------------
+ *
+ * TclStat --
+ *
+ * This procedure replaces the library version of stat and lsat.
+ *
+ * Results:
+ * See stat documentation.
+ *
+ * Side effects:
+ * See stat documentation.
+ *
+ *----------------------------------------------------------------------
+ */
+
+int
+TclStat(path, buf)
+ CONST char *path; /* Path of file to stat (in current CP). */
+ TclStat_ *buf; /* Filled with results of stat call. */
+{
+ StatProcPtr statProcPtr = statProcList;
+ int retVal = -1;
+
+ /*
+ * Call each of the "stat" function in succession. A non-return
+ * value of -1 indicates the particular function has succeeded.
+ */
+
+ while ((retVal == -1) && (statProcPtr != NULL)) {
+ retVal = (*statProcPtr->proc)(path, buf);
+ statProcPtr = statProcPtr->next;
+ }
+
+ return (retVal);
+}
+
+/*
+ *----------------------------------------------------------------------
+ *
+ * TclAccess --
+ *
+ * This procedure replaces the library version of access.
+ *
+ * Results:
+ * See access documentation.
+ *
+ * Side effects:
+ * See access documentation.
+ *
+ *----------------------------------------------------------------------
+ */
+
+int
+TclAccess(path, mode)
+ CONST char *path; /* Path of file to access (in current CP). */
+ int mode; /* Permission setting. */
+{
+ AccessProcPtr accessProcPtr = accessProcList;
+ int retVal = -1;
+
+ /*
+ * Call each of the "access" function in succession. A non-return
+ * value of -1 indicates the particular function has succeeded.
+ */
+
+ while ((retVal == -1) && (accessProcPtr != NULL)) {
+ retVal = (*accessProcPtr->proc)(path, mode);
+ accessProcPtr = accessProcPtr->next;
+ }
+
+ return (retVal);
+}
+
+/*
+ *----------------------------------------------------------------------
+ *
+ * Tcl_OpenFileChannel --
+ *
+ * @@@
+ *
+ * Results:
+ * @@@
+ *
+ * Side effects:
+ * @@@
+ *
+ *----------------------------------------------------------------------
+ */
+
+Tcl_Channel
+Tcl_OpenFileChannel(interp, fileName, modeString, permissions)
+ Tcl_Interp *interp; /* Interpreter for error reporting;
+ * can be NULL. */
+ char *fileName; /* Name of file to open. */
+ char *modeString; /* A list of POSIX open modes or
+ * a string such as "rw". */
+ int permissions; /* If the open involves creating a
+ * file, with what modes to create
+ * it? */
+{
+ OpenFileChannelProcPtr openFileChannelProcPtr = openFileChannelProcList;
+ Tcl_Channel retVal = NULL;
+
+ /*
+ * Call each of the "Tcl_OpenFileChannel" function in succession.
+ * A non-NULL return value indicates the particular function has
+ * succeeded.
+ */
+
+ while ((retVal == NULL) && (openFileChannelProcPtr != NULL)) {
+ retVal = (*openFileChannelProcPtr->proc)(interp, fileName,
+ modeString, permissions);
+ openFileChannelProcPtr = openFileChannelProcPtr->next;
+ }
+
+ return (retVal);
+}
+
+/*
+ *----------------------------------------------------------------------
+ *
+ * TclStatInsertProc --
+ *
+ * @@@
+ *
+ * Results:
+ * @@@
+ *
+ * Side effects:
+ * @@@
+ *
+ *----------------------------------------------------------------------
+ */
+
+int
+TclStatInsertProc (proc)
+ TclStatProc_ *proc;
+{
+ int retVal = TCL_ERROR;
+
+ if (proc != NULL) {
+ StatProcPtr newStatProcPtr;
+
+ newStatProcPtr = (StatProcPtr)Tcl_Alloc(sizeof(StatProc));;
+
+ if (newStatProcPtr != NULL) {
+ newStatProcPtr->proc = proc;
+ newStatProcPtr->next = statProcList;
+ statProcList = newStatProcPtr;
+
+ retVal = TCL_OK;
+ }
+ }
+
+ return (retVal);
+}
+
+/*
+ *----------------------------------------------------------------------
+ *
+ * TclStatDeleteProc --
+ *
+ * @@@
+ *
+ * Results:
+ * @@@
+ *
+ * Side effects:
+ * @@@
+ *
+ *----------------------------------------------------------------------
+ */
+
+int
+TclStatDeleteProc (proc)
+ TclStatProc_ *proc;
+{
+ int retVal = TCL_ERROR;
+ StatProcPtr tmpStatProcPtr = statProcList;
+ StatProcPtr prevStatProcPtr = NULL;
+
+ /*
+ * Traverse the 'statProcList' looking for the particular node
+ * whose 'proc' member matches 'proc' and remove that one from
+ * the list. Ensure that the "default" node cannot be removed.
+ */
+
+ while ((retVal == TCL_ERROR) && (tmpStatProcPtr != &defaultStatProc)) {
+ if (tmpStatProcPtr->proc == proc) {
+ if (prevStatProcPtr == NULL) {
+ statProcList = tmpStatProcPtr->next;
+ } else {
+ prevStatProcPtr->next = tmpStatProcPtr->next;
+ }
+
+ Tcl_Free((char *)tmpStatProcPtr);
+
+ retVal = TCL_OK;
+ } else {
+ prevStatProcPtr = tmpStatProcPtr;
+ tmpStatProcPtr = tmpStatProcPtr->next;
+ }
+ }
+
+ return (retVal);
+}
+
+/*
+ *----------------------------------------------------------------------
+ *
+ * TclAccessInsertProc --
+ *
+ * @@@
+ *
+ * Results:
+ * @@@
+ *
+ * Side effects:
+ * @@@
+ *
+ *----------------------------------------------------------------------
+ */
+
+int
+TclAccessInsertProc(proc)
+ TclAccessProc_ *proc;
+{
+ int retVal = TCL_ERROR;
+
+ if (proc != NULL) {
+ AccessProcPtr newAccessProcPtr;
+
+ newAccessProcPtr = (AccessProcPtr)Tcl_Alloc(sizeof(AccessProc));;
+
+ if (newAccessProcPtr != NULL) {
+ newAccessProcPtr->proc = proc;
+ newAccessProcPtr->next = accessProcList;
+ accessProcList = newAccessProcPtr;
+
+ retVal = TCL_OK;
+ }
+ }
+
+ return (retVal);
+}
+
+/*
+ *----------------------------------------------------------------------
+ *
+ * TclAccessDeleteProc --
+ *
+ * @@@
+ *
+ * Results:
+ * @@@
+ *
+ * Side effects:
+ * @@@
+ *
+ *----------------------------------------------------------------------
+ */
+
+int
+TclAccessDeleteProc(proc)
+ TclAccessProc_ *proc;
+{
+ int retVal = TCL_ERROR;
+ AccessProcPtr tmpAccessProcPtr = accessProcList;
+ AccessProcPtr prevAccessProcPtr = NULL;
+
+ /*
+ * Traverse the 'accessProcList' looking for the particular node
+ * whose 'proc' member matches 'proc' and remove that one from
+ * the list. Ensure that the "default" node cannot be removed.
+ */
+
+ while ((retVal == TCL_ERROR) && (tmpAccessProcPtr != &defaultAccessProc)) {
+ if (tmpAccessProcPtr->proc == proc) {
+ if (prevAccessProcPtr == NULL) {
+ accessProcList = tmpAccessProcPtr->next;
+ } else {
+ prevAccessProcPtr->next = tmpAccessProcPtr->next;
+ }
+
+ Tcl_Free((char *)tmpAccessProcPtr);
+
+ retVal = TCL_OK;
+ } else {
+ prevAccessProcPtr = tmpAccessProcPtr;
+ tmpAccessProcPtr = tmpAccessProcPtr->next;
+ }
+ }
+
+ return (retVal);
+}
+
+/*
+ *----------------------------------------------------------------------
+ *
+ * TclOpenFileChannelInsertProc --
+ *
+ * @@@
+ *
+ * Results:
+ * @@@
+ *
+ * Side effects:
+ * @@@
+ *
+ *----------------------------------------------------------------------
+ */
+
+int
+TclOpenFileChannelInsertProc(proc)
+ TclOpenFileChannelProc_ *proc;
+{
+ int retVal = TCL_ERROR;
+
+ if (proc != NULL) {
+ OpenFileChannelProcPtr newOpenFileChannelProcPtr;
+
+ newOpenFileChannelProcPtr =
+ (OpenFileChannelProcPtr)Tcl_Alloc(sizeof(OpenFileChannelProc));;
+
+ if (newOpenFileChannelProcPtr != NULL) {
+ newOpenFileChannelProcPtr->proc = proc;
+ newOpenFileChannelProcPtr->next = openFileChannelProcList;
+ openFileChannelProcList = newOpenFileChannelProcPtr;
+
+ retVal = TCL_OK;
+ }
+ }
+
+ return (retVal);
+}
+
+/*
+ *----------------------------------------------------------------------
+ *
+ * TclOpenFileChannelDeleteProc --
+ *
+ * @@@
+ *
+ * Results:
+ * @@@
+ *
+ * Side effects:
+ * @@@
+ *
+ *----------------------------------------------------------------------
+ */
+
+int
+TclOpenFileChannelDeleteProc(proc)
+ TclOpenFileChannelProc_ *proc;
+{
+ int retVal = TCL_ERROR;
+ OpenFileChannelProcPtr tmpOpenFileChannelProcPtr = openFileChannelProcList;
+ OpenFileChannelProcPtr prevOpenFileChannelProcPtr = NULL;
+
+ /*
+ * Traverse the 'openFileChannelProcList' looking for the particular
+ * node whose 'proc' member matches 'proc' and remove that one from
+ * the list. Ensure that the "default" node cannot be removed.
+ */
+
+ while ((retVal == TCL_ERROR) &&
+ (tmpOpenFileChannelProcPtr != &defaultOpenFileChannelProc)) {
+ if (tmpOpenFileChannelProcPtr->proc == proc) {
+ if (prevOpenFileChannelProcPtr == NULL) {
+ openFileChannelProcList = tmpOpenFileChannelProcPtr->next;
+ } else {
+ prevOpenFileChannelProcPtr->next = tmpOpenFileChannelProcPtr->next;
+ }
+
+ Tcl_Free((char *)tmpOpenFileChannelProcPtr);
+
+ retVal = TCL_OK;
+ } else {
+ prevOpenFileChannelProcPtr = tmpOpenFileChannelProcPtr;
+ tmpOpenFileChannelProcPtr = tmpOpenFileChannelProcPtr->next;
+ }
+ }
+
+ return (retVal);
+}