Fixes to the appendvfs.c extension. Add the "sqltclsh" application that

uses appendvfs.c to find its scripts.

FossilOrigin-Name: ee248b529c2396c5480fb99b0a1dc31032627ec8241eca4a8c0fff257bb4a088

tool/sqltclsh.c.in

@@ -0,0 +1,42 @@
+/*
+** This is the source code to a "tclsh" that has SQLite built-in.
+**
+** The startup script is located as follows:
+**
+**   (1)  Open the executable as an appended SQLite database and try to
+**        read the startup script out of that database.
+**
+**   (2)  If the first argument is a readable file, try to open that file
+**        as an SQLite database and read the startup script out of that
+**        database.
+**
+**   (3)  If the first argument is a readable file with a ".tcl" extension,
+**        then try to run that script directly.
+**
+** If none of the above steps work, then the program runs as an interactive
+** tclsh.
+*/
+#define TCLSH_INIT_PROC sqlite3_tclapp_init_proc
+#define SQLITE_ENABLE_DBSTAT_VTAB 1
+#undef SQLITE_THREADSAFE
+#define SQLITE_THREADSAFE 0
+#undef SQLITE_ENABLE_COLUMN_METADATA
+#define SQLITE_OMIT_DECLTYPE 1
+#define SQLITE_OMIT_DEPRECATED 1
+#define SQLITE_OMIT_PROGRESS_CALLBACK 1
+#define SQLITE_OMIT_SHARED_CACHE 1
+#define SQLITE_DEFAULT_MEMSTATUS 0
+#define SQLITE_MAX_EXPR_DEPTH 0
+INCLUDE sqlite3.c
+INCLUDE $ROOT/ext/misc/appendvfs.c
+INCLUDE $ROOT/src/tclsqlite.c
+
+const char *sqlite3_tclapp_init_proc(Tcl_Interp *interp){
+  (void)interp;
+  sqlite3_appendvfs_init(0,0,0);
+  return
+BEGIN_STRING
+INCLUDE $ROOT/tool/sqltclsh.tcl
+END_STRING
+;
+}

tool/sqltclsh.tcl

@@ -0,0 +1,66 @@
+# Try to open the executable as a database and read the "scripts.data"
+# field where "scripts.name" is 'main.tcl'
+#
+catch {
+  sqlite3 db $argv0 -vfs apndvfs -create 0
+  set mainscript [db one {SELECT data FROM scripts WHERE name='main.tcl'}]
+}
+if {[info exists mainscript]} {
+  eval $mainscript
+  return
+} else {
+  catch {db close}
+}
+
+# Try to open file named in the first argument as a database and
+# read the "scripts.data" field where "scripts.name" is 'main.tcl'
+#
+if {[llength $argv]>0 && [file readable [lindex $argv 0]]} {
+  catch {
+    sqlite3 db [lindex $argv 0] -vfs apndvfs -create 0
+    set mainscript [db one {SELECT data FROM scripts WHERE name='main.tcl'}]
+    set argv0 [lindex $argv 0]
+    set argv [lrange $argv 1 end]
+  }
+  if {[info exists mainscript]} {
+    eval $mainscript
+    return
+  } else {
+    catch {db close}
+  }
+  if {[string match *.tcl [lindex $argv 0]]} {
+    set fd [open [lindex $argv 0] rb]
+    set mainscript [read $fd]
+    close $fd
+    unset fd
+    set argv0 [lindex $argv 0]
+    set argv [lrange $argv 1 end]
+  }
+  if {[info exists mainscript]} {
+    eval $mainscript
+    return
+  }
+}
+
+# If all else fails, do an interactive loop
+#
+set line {}
+while {![eof stdin]} {
+  if {$line!=""} {
+    puts -nonewline "> "
+  } else {
+    puts -nonewline "% "
+  }
+  flush stdout
+  append line [gets stdin]
+  if {[info complete $line]} {
+    if {[catch {uplevel #0 $line} result]} {
+      puts stderr "Error: $result"
+    } elseif {$result!=""} {
+      puts $result
+    }
+    set line {}
+  } else {
+    append line \\n"
+  }
+}