# System autoconfiguration. Try: ./configure --help

# This must be above "options" below because it implicitly brings in the
# default Autosetup options, things like --prefix.
use cc cc-lib

options {
    with-openssl:path|auto|tree|none
                         => {Look for OpenSSL in the given path, automatically, in the source tree, or none}
    with-zlib:path|auto|tree
                         => {Look for zlib in the given path, automatically, or in the source tree}
    with-sqlite:path|auto|tree
                         => {Look for sqlite in the given path, automatically, or in the source tree.}
    with-exec-rel-paths=0
                         => {Enable relative paths for external diff/gdiff}
    with-sanitizer:      => {Build with C compiler's -fsanitize=LIST; e.g. address,enum,null,undefined}
    with-th1-docs=0      => {Enable TH1 for embedded documentation pages}
    with-th1-hooks=0     => {Enable TH1 hooks for commands and web pages}
    with-tcl:path        => {Enable Tcl integration, with Tcl in the specified path}
    with-tcl-stubs=0     => {Enable Tcl integration via stubs library mechanism}
    with-tcl-private-stubs=0
                         => {Enable Tcl integration via private stubs mechanism}
    with-mman=0          => {Enable use of POSIX memory APIs from "sys/mman.h"}
    with-see=0           => {Enable the SQLite Encryption Extension (SEE)}
    print-minimum-sqlite-version=0
                         => {print the minimum SQLite version number required, and exit}
    internal-sqlite=1    => {Don't use the internal SQLite, use the system one}
    static=0             => {Link a static executable}
    fusefs=1             => {Disable the Fuse Filesystem}
    fossil-debug=0       => {Build with fossil debugging enabled}
    no-opt=0             => {Build without optimization}
    json=0               => {Build with fossil JSON API enabled}
    with-emsdk:path      => {Directory containing the Emscripten SDK}
    compile-commands=0 =>
      "Check for compile_commands.json support."
}

# Update the minimum required SQLite version number here, and also
# in src/main.c near the sqlite3_libversion_number() call.  Take care
# that both places agree!
define MINIMUM_SQLITE_VERSION "3.46.0"

# This is useful for people wanting Fossil to use an external SQLite library
# to compare the one they have against the minimum required
if {[opt-bool print-minimum-sqlite-version]} {
    puts [get-define MINIMUM_SQLITE_VERSION]
    exit 0
}

set outOfTreeBuild 0
if {![file exists fossil.1]} {
  puts "This appears to be an out-of-tree build."
  set outOfTreeBuild 1
}

# sqlite wants these types if possible
cc-with {-includes {stdint.h inttypes.h}} {
    cc-check-types uint32_t uint16_t int16_t uint8_t
}

# Use pread/pwrite system calls in place of seek + read/write if possible
define USE_PREAD [cc-check-functions pread]

# If we have cscope here, we'll use it in the "tags" target
if {[cc-check-progs cscope]} {
    define COLLECT_CSCOPE_DATA "cscope -bR $::autosetup(srcdir)/src/*.\[ch\]"
} else {
    define COLLECT_CSCOPE_DATA ""
}

# Find tclsh for the test suite.
#
# We can't use jimsh for this: the test suite uses features of Tcl that
# Jim doesn't support, either statically or due to the way it's built by
# autosetup.  For example, Jim supports `file normalize`, but only if
# you build it with HAVE_REALPATH, which won't ever be defined in this
# context because autosetup doesn't try to discover platform-specific
# details like that before it decides to build jimsh0.  Besides which,
# autosetup won't build jimsh0 at all if it can find tclsh itself.
# Ironically, this means we may right now be running under either jimsh0
# or a version of tclsh that we find unsuitable below!
cc-check-progs tclsh
set hbtd /usr/local/Cellar/tcl-tk
if {[string equal false [get-define TCLSH]]} {
    msg-result "WARNING: 'make test' will not run here."
} else {
    set v [exec /bin/sh -c "echo 'puts \$tcl_version' | tclsh"]
    if {[expr {$v >= 8.6}]} {
        msg-result "Found Tclsh version $v in the PATH."
        define TCLSH tclsh
    } elseif {[file isdirectory $hbtd]} {
        # This is a macOS system with the Homebrew version of Tcl/Tk
        # installed.  Select the newest version.  It won't normally be
        # in the PATH to avoid shadowing /usr/bin/tclsh, and even if it
        # were in the PATH, it's bad practice to put /usr/local/bin (the
        # Homebrew default) ahead of /usr/bin, especially given that
        # it's user-writeable by default with Homebrew.  Thus, we can be
        # pretty sure the only way to call it is with an absolute path.
        set v [exec ls -tr $hbtd | tail -1]
        set path "$hbtd/$v/bin/tclsh"
        define TCLSH $path
        msg-result "Using Homebrew Tcl/Tk version $path."
    } else {
        msg-result "WARNING: tclsh $v found; need >= 8.6 for 'make test'."
        define TCLSH false     ;# force "make test" failure via /usr/bin/false
    }
}

define EXTRA_CFLAGS "-Wall"
define EXTRA_LDFLAGS ""
define USE_SYSTEM_SQLITE 0
define USE_LINENOISE 0
define USE_MMAN_H 0
define USE_SEE 0
define SQLITE3_ORIGIN 0
# SQLITE3_ORIGIN 0 = src/sqlite3, 1=src/sqlite3-see.c, 2=client-provided
define SQLITE_OPTIONS_EXT ""
# SQLITE_OPTIONS_EXT => build-dependent CFLAGS for sqlite3.c and shell.c

# Maintain the C89/C90-style order of variable declarations before statements.
# Check if the compiler supports the respective warning flag.
if {[cctest -cflags -Wdeclaration-after-statement]} {
    define-append EXTRA_CFLAGS -Wdeclaration-after-statement
}


# This procedure is a customized version of "cc-check-function-in-lib",
# that does not modify the LIBS variable.  Its use prevents prematurely
# pulling in libraries that will be added later anyhow (e.g. "-ldl").
proc check-function-in-lib {function libs {otherlibs {}}} {
    if {[string length $otherlibs]} {
        msg-checking "Checking for $function in $libs with $otherlibs..."
    } else {
        msg-checking "Checking for $function in $libs..."
    }
    set found 0
    cc-with [list -libs $otherlibs] {
        if {[cctest_function $function]} {
            msg-result "none needed"
            define lib_$function ""
            incr found
        } else {
            foreach lib $libs {
                cc-with [list -libs -l$lib] {
                    if {[cctest_function $function]} {
                        msg-result -l$lib
                        define lib_$function -l$lib
                        incr found
                        break
                    }
                }
            }
        }
    }
    if {$found} {
        define [feature-define-name $function]
    } else {
        msg-result "no"
    }
    return $found
}

if {![opt-bool internal-sqlite]} {
  proc find_system_sqlite {} {

    # On some systems (slackware), libsqlite3 requires -ldl to link. So
    # search for the system SQLite once with -ldl, and once without. If
    # the library can only be found with $extralibs set to -ldl, then
    # the code below will append -ldl to LIBS.
    #
    foreach extralibs {{} {-ldl}} {

      # Locate the system SQLite by searching for sqlite3_open(). Then check
      # if sqlite3_stmt_isexplain can be found as well. If we can find open() but
      # not stmt_isexplain(), then the system SQLite is too old to link against
      # fossil.
      #
      if {[check-function-in-lib sqlite3_open sqlite3 $extralibs]} {
        # Success. Update symbols and return.
        #
        define USE_SYSTEM_SQLITE 1
        define-append LIBS -lsqlite3
        define-append LIBS $extralibs
        return
      }
    }
    user-error "system sqlite3 not found"
  }

  find_system_sqlite

  proc test_system_sqlite {} {
    # Check compatibility of the system SQLite library by running the
    # sqlcompttest.c program in the source tree passes
    # MINIMUM_SQLITE_VERSION set at the top of this file to
    # sqlcompttest.c
    #
    set cmdline {}
    lappend cmdline {*}[get-define CCACHE]
    lappend cmdline {*}[get-define CC] {*}[get-define CFLAGS]
    lappend cmdline $::autosetup(dir)/../tools/sqlcompattest.c -o conftest__
    lappend cmdline {*}[get-define LDFLAGS]
    lappend cmdline {*}[get-define LIBS]
    set sqlite-version [string cat "-D MINIMUM_SQLITE_VERSION=" [get-define MINIMUM_SQLITE_VERSION]]
    lappend cmdline {*}[set sqlite-version]
    set ok 1
    set err [catch {exec-with-stderr {*}$cmdline} result errinfo]
    if {$err} {
       configlog "Failed: [join $cmdline]"
       if {[string length $result]>0} {configlog $result}
       configlog "============"
       set ok 0
    } elseif {$::autosetup(debug)} {
       configlog "Compiled OK: [join $cmdline]"
       configlog "============"
    }
    if {!$ok} {
      user-error "unable to compile SQLite compatibility test program"
    }
    set err [catch {exec-with-stderr ./conftest__} result errinfo]
    if {[get-define build] eq [get-define host]} {
      set err [catch {exec-with-stderr ./conftest__} result errinfo]
      if {$err} {
        user-error $result
      }
    }
    file delete ./conftest__
  }
  test_system_sqlite

}

proc is_mingw {} {
    return [string match *mingw* [get-define host]]
}

if {[is_mingw]} {
    define-append EXTRA_CFLAGS -DBROKEN_MINGW_CMDLINE
    define-append LIBS -lkernel32 -lws2_32
} else {
    #
    # NOTE: All platforms except MinGW should use the linenoise
    #       package.  It is currently unsupported on Win32.
    #
    define USE_LINENOISE 1
}

if {[string match *-solaris* [get-define host]]} {
    define-append EXTRA_CFLAGS {-D__EXTENSIONS__}
}

if {[opt-bool fossil-debug]} {
    define CFLAGS {-g -O0 -Wall}
    define-append CFLAGS -DFOSSIL_DEBUG
    msg-result "Debugging support enabled"
}

if {[opt-bool no-opt]} {
    define CFLAGS {-g -O0 -Wall}
    msg-result "Builting without compiler optimization"
    if {[opt-bool fossil-debug]} {
        define-append CFLAGS -DFOSSIL_DEBUG
    }
}

if {[opt-bool with-mman]} {
    define-append EXTRA_CFLAGS -DUSE_MMAN_H
    define USE_MMAN_H 1
    msg-result "Enabling \"sys/mman.h\" support"
}

if {[opt-bool with-see]} {
    define-append EXTRA_CFLAGS -DUSE_SEE
    define USE_SEE 1
    define SQLITE3_ORIGIN 1
    msg-result "Enabling encryption support"
}

if {[opt-bool json]} {
    # Reminder/FIXME (stephan): FOSSIL_ENABLE_JSON
    # is required in the CFLAGS because json*.c
    # have #ifdef guards around the whole file without
    # reading config.h first.
    define-append EXTRA_CFLAGS -DFOSSIL_ENABLE_JSON
    define FOSSIL_ENABLE_JSON
    msg-result "JSON support enabled"
}

if {[opt-bool with-exec-rel-paths]} {
    define-append EXTRA_CFLAGS -DFOSSIL_ENABLE_EXEC_REL_PATHS
    define FOSSIL_ENABLE_EXEC_REL_PATHS
    msg-result "Relative paths in external diff/gdiff enabled"
}

if {[opt-bool with-th1-docs]} {
    define-append EXTRA_CFLAGS -DFOSSIL_ENABLE_TH1_DOCS
    define FOSSIL_ENABLE_TH1_DOCS
    msg-result "TH1 embedded documentation support enabled"
}

if {[opt-bool with-th1-hooks]} {
    define-append EXTRA_CFLAGS -DFOSSIL_ENABLE_TH1_HOOKS
    define FOSSIL_ENABLE_TH1_HOOKS
    msg-result "TH1 hooks support enabled"
}

#if {[opt-bool markdown]} {
#    # no-op.  Markdown is now enabled by default.
#    msg-result "Markdown support enabled"
#}

if {[opt-bool static]} {
    # XXX: This will not work on all systems.
    define-append EXTRA_LDFLAGS -static
    msg-result "Trying to link statically"
} else {
    define-append EXTRA_CFLAGS -DFOSSIL_DYNAMIC_BUILD=1
    define FOSSIL_DYNAMIC_BUILD
}

# Check for libraries that need to be sorted out early
cc-check-function-in-lib iconv iconv

# Helper for OpenSSL checking
proc check-for-openssl {msg {cflags {}} {libs {-lssl -lcrypto -lpthread}}} {
    msg-checking "Checking for $msg..."
    set rc 0
    if {[is_mingw]} {
        lappend libs -lgdi32 -lwsock32 -lcrypt32
    }
    if {[info exists ::zlib_lib]} {
        lappend libs $::zlib_lib
    }
    msg-quiet cc-with [list -cflags $cflags -libs $libs] {
        if {[cc-check-includes openssl/ssl.h] && \
                [cc-check-functions SSL_new]} {
            incr rc
        }
    }
    if {!$rc && ![is_mingw]} {
        # On some systems, OpenSSL appears to require -ldl to link.
        lappend libs -ldl
        msg-quiet cc-with [list -cflags $cflags -libs $libs] {
            if {[cc-check-includes openssl/ssl.h] && \
                    [cc-check-functions SSL_new]} {
                incr rc
            }
        }
    }
    if {$rc} {
        msg-result "ok"
        return 1
    } else {
        msg-result "no"
        return 0
    }
}

# Check for zlib, using the given location if specified
set zlibpath [opt-val with-zlib]
if {$zlibpath eq "tree"} {
  set zlibdir [file dirname $autosetup(dir)]/compat/zlib
  if {![file isdirectory $zlibdir]} {
    user-error "The zlib in source tree directory does not exist"
  } elseif { ([llength [glob -nocomplain -directory $zlibdir libz*]] == 0) } {
    user-error "With --with-zlib=tree, $zlibdir must be configured and built first."
  }
  cc-with [list -cflags "-I$zlibdir -L$zlibdir"]
  define-append EXTRA_CFLAGS -I$zlibdir
  define-append LIBS $zlibdir/libz.a
  set ::zlib_lib $zlibdir/libz.a
  msg-result "Using zlib in source tree"
} else {
  set cftry {""}
  set ldtry {""}
  if {$zlibpath ni {auto ""}} {
    lappend cftry "-I$zlibpath"
    lappend cftry "-I$zlibpath/include"
    lappend ldtry "-L$zlibpath"
    lappend ldtry "-L$zlibpath/lib"
  }

  # Reverse the list of tests so we check most-specific to least, else
  # platform devel files will shadow local --with-zlib overrides.
  foreach c [lreverse $cftry] {
    if {[cc-with [list -cflags $c] {cc-check-includes zlib.h}]} {
      if {$c eq ""} {
        msg-result "Found zlib.h in default include path"
      } else {
        define-append EXTRA_CFLAGS "$c"
        msg-result "Found zlib.h via $c"
      }
      set cfound $c
      break
    }
  }
  if {![info exists cfound]} {
    user-error "zlib.h not found; either install it or specify its location via --with-zlib"
  }
  foreach lcheck [lreverse $ldtry] {
    if {[cc-with [list -cflags "$cfound $lcheck"] {check-function-in-lib inflateEnd z}]} {
      if {$lcheck eq ""} {
        msg-result "Linked to zlib via default library path"
      } else {
        define-append EXTRA_LDFLAGS "$lcheck"
        msg-result "Linked to zlib via $lcheck"
      }
      if {![check-function-in-lib compressBound z]} {
        puts "Notice: disabling zlib compression in the SQL shell"
        define-append SQLITE_OPTIONS_EXT {-USQLITE_HAVE_ZLIB}
      }
      break
    }
  }
  set ::zlib_lib -lz
}

set ssldirs [opt-val with-openssl]
if {$ssldirs ne "none"} {
    set found 0
    if {$ssldirs eq "tree"} {
        set ssldir [file dirname $autosetup(dir)]/compat/openssl
        if {![file isdirectory $ssldir]} {
            user-error "The OpenSSL in source tree directory does not exist"
        }
        set msg "ssl in $ssldir"
        set cflags "-I$ssldir/include"
        set ldflags "-L$ssldir"
        set ssllibs "$ssldir/libssl.a $ssldir/libcrypto.a -lpthread"
        set found [check-for-openssl "ssl in source tree" "$cflags $ldflags" $ssllibs]
    } else {
        if {$ssldirs in {auto ""}} {
            catch {
                set cflags [exec pkg-config openssl --cflags-only-I]
                set ldflags [exec pkg-config openssl --libs-only-L]
                set found [check-for-openssl "ssl via pkg-config" "$cflags $ldflags"]
            } msg
            if {!$found} {
                set ssldirs "{} /usr/sfw /usr/local/ssl /usr/lib/ssl /usr/ssl \
                             /usr/pkg /usr/local /usr /usr/local/opt/openssl \
                             /opt/homebrew/opt/openssl"
            }
        }
        if {!$found} {
            foreach dir $ssldirs {
                if {$dir eq ""} {
                    set msg "system ssl"
                    set cflags ""
                    set ldflags ""
                } else {
                    set msg "ssl in $dir"
                    set cflags "-I$dir/include"
                    set ldflags "-L$dir/lib"
                }
                if {[check-for-openssl $msg "$cflags $ldflags"]} {
                    incr found
                    break
                }
            }
        }
    }
    if {$found} {
        define FOSSIL_ENABLE_SSL
        define-append EXTRA_CFLAGS $cflags
        define-append EXTRA_LDFLAGS $ldflags
        define-append CFLAGS $cflags
        define-append LDFLAGS $ldflags
        if {[info exists ssllibs]} {
            define-append LIBS $ssllibs
        } else {
            define-append LIBS -lssl -lcrypto
        }
        if {[info exists ::zlib_lib]} {
            define-append LIBS $::zlib_lib
        }
        if {[is_mingw]} {
            define-append LIBS -lgdi32 -lwsock32 -lcrypt32
        }
        msg-result "HTTPS support enabled"

        # Silence OpenSSL deprecation warnings on Mac OS X 10.7.
        if {[string match *-darwin* [get-define host]]} {
            if {[cctest -cflags {-Wdeprecated-declarations}]} {
                define-append EXTRA_CFLAGS -Wdeprecated-declarations
            }
        }
    } else {
        user-error "OpenSSL not found. Consider --with-openssl=none to disable HTTPS support"
    }
} else {
    if {[info exists ::zlib_lib]} {
        define-append LIBS $::zlib_lib
    }
}



########################################################################
# --with-sqlite=PATH checks for the first it finds of the following...
# - PATH/sqlite3.c and PATH/sqlite3.h
# - PATH/sqlite3.o (and assumes sqlite3.h is with it)
# - PATH/lib/libsqlite3* and PATH/include/sqlite3.h
define CFLAGS_INCLUDE {}
# ^^^ CFLAGS_INCLUDE is ONLY for -I... flags and their order is
# significant so that --with-sqlite=PATH's header can shadow our
# own. One caveat with this is that we cannot point --with-sqlite=PATH
# to the root of sqlite3's own build tree because that dir has a
# config.h which ends up shadowing src/config.h, breaking our build.
set sq3path [opt-val with-sqlite]
define SQLITE3_SRC.2 {}
define SQLITE3_OBJ.2 {}
define SQLITE3_SHELL_SRC.2 {$(SQLITE3_SHELL_SRC.0)}
if {$sq3path in {tree ""}} {
  msg-result "Using sqlite3.c from this source tree."
} else {
  # SQLITE3_ORIGIN:
  #   0 = local source tree
  #   1 = use external lib or sqlite3.o
  #   2 = use external sqlite3.c and (if found) shell.c
  define USE_SYSTEM_SQLITE 1
  define SQLITE3_ORIGIN 2
  if {$sq3path != "auto"} {
    if {([file exists $sq3path/sqlite3.c]) && \
        ([file exists $sq3path/sqlite3.h]) } {
      # Prefer sqlite3.[ch] if found.
      define SQLITE3_SRC.2 $sq3path/sqlite3.c
      define SQLITE3_OBJ.2 {$(SQLITE3_OBJ.0)}
      define USE_SYSTEM_SQLITE 2
      define SQLITE3_ORIGIN 2
      if {[file exists $sq3path/shell.c]} {
        define SQLITE3_SHELL_SRC.2 $sq3path/shell.c
      }
      define-append CFLAGS_INCLUDE -I$sq3path
      define-append EXTRA_LDFLAGS -lpthread
      # ^^^ additional -lXXX flags are conservative estimates
      msg-result "Using sqlite3.c and sqlite3.h from $sq3path"
    } elseif {[file exists $sq3path/sqlite3.o]} {
      # Use sqlite3.o if found.
      define SQLITE3_OBJ.2 $sq3path/sqlite3.o
      define-append CFLAGS_INCLUDE -I$sq3path
      define-append EXTRA_LDFLAGS $sq3path/sqlite3.o -lpthread
      # ^^^ additional -lXXX flags are conservative estimates
      msg-result "Using sqlite3.o from $sq3path"
    } elseif { ([llength [glob -nocomplain -directory $sq3path/lib libsqlite3*]] != 0) \
                 && ([file exists $sq3path/include/sqlite3.h]) } {
      # e.g. --with-sqlite=/usr/local. Try $sq3path/lib/libsqlite3*
      # and $sq3path/include/sqlite3.h
      define-append CFLAGS_INCLUDE -I$sq3path/include
      define-append EXTRA_LDFLAGS -L$sq3path/lib -lsqlite3 -lpthread
      # ^^^ additional -lXXX flags are conservative estimates
      msg-result "Using -lsqlite3 from $sq3path"
    } else {
      # Assume $sq3path holds both the lib and header
      cc-with [list -cflags "-I$sq3path -L$sq3path"]
      define-append CFLAGS_INCLUDE -I$sq3path
      define-append EXTRA_LDFLAGS -L$sq3path -lsqlite3 -lpthread
      # ^^^ additional -lXXX flags are conservative estimates
      msg-result "Using -lsqlite3 from $sq3path"
    }
  } elseif {![cc-check-includes sqlite3.h] || ![check-function-in-lib sqlite3_open_v2 sqlite3]} {
    user-error "libsqlite3 not found please install it or specify the location with --with-sqlite"
  }
}
define-append CFLAGS_INCLUDE {-I. -I$(SRCDIR) -I$(SRCDIR_extsrc)}

set tclpath [opt-val with-tcl]
if {$tclpath ne ""} {
    set tclprivatestubs [opt-bool with-tcl-private-stubs]
    # Note parse-tclconfig-sh is in autosetup/local.tcl
    if {$tclpath eq "1"} {
        set tcldir [file dirname $autosetup(dir)]/compat/tcl-8.6
        if {$tclprivatestubs} {
            set tclconfig(TCL_INCLUDE_SPEC) -I$tcldir/generic
            set tclconfig(TCL_VERSION) {Private Stubs}
            set tclconfig(TCL_PATCH_LEVEL) {}
            set tclconfig(TCL_PREFIX) $tcldir
            set tclconfig(TCL_LD_FLAGS) { }
        } else {
            # Use the system Tcl. Look in some likely places.
            array set tclconfig [parse-tclconfig-sh \
                $tcldir/unix $tcldir/win \
                /usr /usr/local /usr/share /opt/local]
            set msg "on your system"
        }
    } else {
        array set tclconfig [parse-tclconfig-sh $tclpath]
        set msg "at $tclpath"
    }
    if {[opt-bool static]} {
        set tclconfig(TCL_LD_FLAGS) { }
    }
    if {![info exists tclconfig(TCL_INCLUDE_SPEC)]} {
        user-error "Cannot find Tcl $msg"
    }
    set tclstubs [opt-bool with-tcl-stubs]
    if {$tclprivatestubs} {
        define FOSSIL_ENABLE_TCL_PRIVATE_STUBS
        define USE_TCL_STUBS
    } elseif {$tclstubs && $tclconfig(TCL_SUPPORTS_STUBS)} {
        set libs "$tclconfig(TCL_STUB_LIB_SPEC)"
        define FOSSIL_ENABLE_TCL_STUBS
        define USE_TCL_STUBS
    } else {
        set libs "$tclconfig(TCL_LIB_SPEC) $tclconfig(TCL_LIBS)"
    }
    set cflags $tclconfig(TCL_INCLUDE_SPEC)
    if {!$tclprivatestubs} {
        set foundtcl 0; # Did we find a working Tcl library?
        cc-with [list -cflags $cflags -libs $libs] {
            if {$tclstubs} {
                if {[cc-check-functions Tcl_InitStubs]} {
                    set foundtcl 1
                }
            } else {
                if {[cc-check-functions Tcl_CreateInterp]} {
                    set foundtcl 1
                }
            }
        }
        if {!$foundtcl && [string match *-lieee* $libs]} {
            # On some systems, using "-lieee" from TCL_LIB_SPEC appears
            # to cause issues.
            msg-result "Removing \"-lieee\" and retrying for Tcl..."
            set libs [string map [list -lieee ""] $libs]
            cc-with [list -cflags $cflags -libs $libs] {
                if {$tclstubs} {
                    if {[cc-check-functions Tcl_InitStubs]} {
                        set foundtcl 1
                    }
                } else {
                    if {[cc-check-functions Tcl_CreateInterp]} {
                        set foundtcl 1
                    }
                }
            }
        }
        if {!$foundtcl && ![string match *-lpthread* $libs]} {
            # On some systems, TCL_LIB_SPEC appears to be missing
            # "-lpthread".  Try adding it.
            msg-result "Adding \"-lpthread\" and retrying for Tcl..."
            set libs "$libs -lpthread"
            cc-with [list -cflags $cflags -libs $libs] {
                if {$tclstubs} {
                    if {[cc-check-functions Tcl_InitStubs]} {
                        set foundtcl 1
                    }
                } else {
                    if {[cc-check-functions Tcl_CreateInterp]} {
                        set foundtcl 1
                    }
                }
            }
        }
        if {!$foundtcl} {
            if {$tclstubs} {
                user-error "Cannot find a usable Tcl stubs library $msg"
            } else {
                user-error "Cannot find a usable Tcl library $msg"
            }
        }
    }
    set version $tclconfig(TCL_VERSION)$tclconfig(TCL_PATCH_LEVEL)
    msg-result "Found Tcl $version at $tclconfig(TCL_PREFIX)"
    if {!$tclprivatestubs} {
        define-append LIBS $libs
    }
    define-append EXTRA_CFLAGS $cflags
    define-append CFLAGS $cflags
    if {[info exists zlibpath] && $zlibpath eq "tree"} {
      #
      # NOTE: When using zlib in the source tree, prevent Tcl from
      #       pulling in the system one.
      #
      set tclconfig(TCL_LD_FLAGS) [string map [list -lz ""] \
          $tclconfig(TCL_LD_FLAGS)]
    }
    #
    # NOTE: Remove "-ldl" from the TCL_LD_FLAGS because it will be
    #       be checked for near the bottom of this file.
    #
    set tclconfig(TCL_LD_FLAGS) [string map [list -ldl ""] \
        $tclconfig(TCL_LD_FLAGS)]
    define-append EXTRA_LDFLAGS $tclconfig(TCL_LD_FLAGS)
    define FOSSIL_ENABLE_TCL
}

# Emscripten is a purely optional component used only for doing
# in-tree builds of WASM stuff, as opposed to WASM binaries we import
# from other places. This is only set up for Unix-style OSes and is
# untested anywhere but Linux.
set emsdkHome [opt-val with-emsdk]
define EMSDK_HOME ""
define EMSDK_ENV ""
define EMCC_OPT "-Oz"
if {$emsdkHome eq "" && [info exists ::env(EMSDK)]} {
  # Fall back to checking the environment. $EMSDK gets set
  # by sourcing emsdk_env.sh.
  set emsdkHome $::env(EMSDK)
}
if {$emsdkHome ne ""} {
  define EMSDK_HOME $emsdkHome
  set emsdkEnv "$emsdkHome/emsdk_env.sh"
  if {[file exists $emsdkEnv]} {
    puts "Using Emscripten SDK environment from $emsdkEnv."
    define EMSDK_ENV $emsdkEnv
    if {[info exists ::env(EMCC_OPT)]} {
      define EMCC_OPT $::env(EMCC_OPT)
    }
  } else {
    puts "emsdk_env.sh not found. Assuming emcc is in the PATH."
  }
}

# Network functions require libraries on some systems
cc-check-function-in-lib gethostbyname nsl
if {![cc-check-function-in-lib socket {socket network}]} {
    # Last resort, may be Windows
    if {[is_mingw]} {
        define-append LIBS -lwsock32
    }
}

# The SMTP module requires special libraries and headers for MX DNS
# record lookups and such.
cc-check-includes arpa/nameser.h
cc-include-needs bind/resolv.h netinet/in.h
cc-check-includes bind/resolv.h
cc-check-includes resolv.h
if {    !(([cc-check-function-in-lib dn_expand resolv] ||
           [cc-check-function-in-lib   ns_name_uncompress {bind resolv}] ||
           [cc-check-function-in-lib __ns_name_uncompress {bind resolv}]) &&
          ([cc-check-function-in-lib   ns_parserr {bind resolv}] ||
           [cc-check-function-in-lib __ns_parserr {bind resolv}]) &&
          ([cc-check-function-in-lib   res_query {bind resolv}] ||
           [cc-check-function-in-lib __res_query {bind resolv}]))} {
    msg-result "WARNING: SMTP feature will not be able to look up local MX."
}
cc-check-function-in-lib res_9_ns_initparse resolv

# Other nonstandard function checks
cc-check-functions utime
cc-check-functions usleep
cc-check-functions strchrnul
cc-check-functions pledge
cc-check-functions backtrace

# Termux on Android adds "getpass(char *)" to unistd.h, so check this so we
# guard against including it again; use cctest as cc-check-functions and 
# cctest_function check for "getpass()" with no args and fail
if {[cctest -link 1 -includes {unistd.h} -code "getpass(0);"]} {
    define FOSSIL_HAVE_GETPASS 1
    msg-result "Found getpass() with unistd.h"
}

# Check for getloadavg(), and if it doesn't exist, define FOSSIL_OMIT_LOAD_AVERAGE
if {![cc-check-functions getloadavg] ||
    ![cctest -link 1 -includes {unistd.h} -code "double a\[3\]; getloadavg(a,3);"]} {
  define FOSSIL_OMIT_LOAD_AVERAGE 1
  msg-result "Load average support unavailable"
}

# Check for getpassphrase() for Solaris 10 where getpass() truncates to 10 chars
if {![cc-check-functions getpassphrase]} {
    # Haiku needs this
    cc-check-function-in-lib getpass bsd
}
cc-check-function-in-lib sin m

# Check for the FuseFS library
if {[opt-bool fusefs]} {
  if {[opt-bool static]} {
     msg-result "FuseFS support disabled due to -static"
  } elseif {[cc-check-function-in-lib fuse_mount fuse]} {
     define-append EXTRA_CFLAGS -DFOSSIL_HAVE_FUSEFS
     define FOSSIL_HAVE_FUSEFS 1
     msg-result "FuseFS support enabled"
  }
}

########################################################################
# Checks the compiler for compile_commands.json support.
#
# Returns 1 if supported, else 0. Defines MAKE_COMPILATION_DB to "yes"
# if supported, "no" if not.
proc check-compile-commands {} {
    msg-checking "compile_commands.json support... "
    if {[cctest -lang c -cflags {/dev/null -MJ} -source {}]} {
        # This test reportedly incorrectly succeeds on one of
        # Martin G.'s older systems.
        msg-result "compiler supports compile_commands.json"
        define MAKE_COMPILATION_DB yes
        return 1
    } else {
        msg-result "compiler does not support compile_commands.json"
        define MAKE_COMPILATION_DB no
        return 0
    }
}

define MAKE_COMPILATION_DB no
if {!$outOfTreeBuild} {
  if {[opt-bool compile-commands]} {
    check-compile-commands
  } else {
    puts "Use --compile-commands to enable check for compile-commands-capable compiler."
  }
} else {
  puts "Disabling compile_commands.json check for out-of-tree build."
  # This is an attempt to resolve the problem reported at
  # https://fossil-scm.org/forum/forumpost/d19061d09a8179d0
}

# Add -fsanitize compile and link options late: we don't want the C
# checks above to run with those sanitizers enabled.  It can not only
# be pointless, it can actually break correct tests.
set fsan [opt-val with-sanitizer]
if {[string length $fsan]} {
    define-append  EXTRA_CFLAGS -fsanitize=$fsan
    define-append EXTRA_LDFLAGS -fsanitize=$fsan
    if {[string first "undefined" $fsan] != -1} {
        # We need to link with libubsan if we're compiling under
        # GCC with -fsanitize=undefined.
        cc-check-function-in-lib __ubsan_handle_add_overflow ubsan
    }
}

# Finally, append libraries that must be last. This matters more on some
# OSes than others, but is most broadly required for static linking.
if {[check-function-in-lib dlopen dl]} {
    # Some platforms (*BSD) have the dl functions already in libc and no libdl.
    # In such case we can link directly without -ldl.
    define-append LIBS [get-define lib_dlopen]
}
if {[opt-bool static]} {
    # Linux can only infer the dependency on pthread from OpenSSL when
    # doing dynamic linkage.
    define-append LIBS -lpthread
}

if {[get-define EMSDK_HOME] ne ""} {
  define EMCC_WRAPPER $::autosetup(dir)/../tools/emcc.sh
  make-template tools/emcc.sh.in
  catch {exec chmod u+x tools/emcc.sh}
} else {
  define EMCC_WRAPPER ""
  catch {exec rm -f tools/emcc.sh}
}

# Tag container builds with a prefix of the checkin ID of the version
# of Fossil each one contains.  This not only allows multiple images
# to coexist and multiple containers to be created unamgiguosly from
# them, it also changes the URL we fetch the source tarball from, so
# repeated builds of a given version generate and fetch the source
# tarball once only, keeping it in the local Docker/Podman cache.
set ci [readfile "$::autosetup(srcdir)/manifest.uuid"]
define FOSSIL_CI_PFX [string range $ci 0 11]

make-template Makefile.in
make-config-header autoconfig.h -auto {USE_* FOSSIL_*}
