split: replace internal packages with images library

Remove all the internal package that are now in the
github.com/osbuild/images package and vendor it.

A new function in internal/blueprint/ converts from an osbuild-composer
blueprint to an images blueprint.  This is necessary for keeping the
blueprint implementation in both packages.  In the future, the images
package will change the blueprint (and most likely rename it) and it
will only be part of the osbuild-composer internals and interface.  The
Convert() function will be responsible for converting the blueprint into
the new configuration object.

vendor/github.com/osbuild/images/internal/common/helpers.go

@@ -0,0 +1,103 @@
+package common
+
+import (
+	"fmt"
+	"io"
+	"regexp"
+	"runtime"
+	"sort"
+	"strconv"
+	"strings"
+)
+
+var RuntimeGOARCH = runtime.GOARCH
+
+func CurrentArch() string {
+	if RuntimeGOARCH == "amd64" {
+		return "x86_64"
+	} else if RuntimeGOARCH == "arm64" {
+		return "aarch64"
+	} else if RuntimeGOARCH == "ppc64le" {
+		return "ppc64le"
+	} else if RuntimeGOARCH == "s390x" {
+		return "s390x"
+	} else {
+		panic("unsupported architecture")
+	}
+}
+
+func PanicOnError(err error) {
+	if err != nil {
+		panic(err)
+	}
+}
+
+// IsStringInSortedSlice returns true if the string is present, false if not
+// slice must be sorted
+func IsStringInSortedSlice(slice []string, s string) bool {
+	i := sort.SearchStrings(slice, s)
+	if i < len(slice) && slice[i] == s {
+		return true
+	}
+	return false
+}
+
+// DataSizeToUint64 converts a size specified as a string in KB/KiB/MB/etc. to
+// a number of bytes represented by uint64.
+func DataSizeToUint64(size string) (uint64, error) {
+	// Pre-process the input
+	size = strings.TrimSpace(size)
+
+	// Get the number from the string
+	plain_number := regexp.MustCompile(`[[:digit:]]+`)
+	number_as_str := plain_number.FindString(size)
+	if number_as_str == "" {
+		return 0, fmt.Errorf("the size string doesn't contain any number: %s", size)
+	}
+
+	// Parse the number into integer
+	return_size, err := strconv.ParseUint(number_as_str, 10, 64)
+	if err != nil {
+		return 0, fmt.Errorf("failed to parse size as integer: %s", number_as_str)
+	}
+
+	// List of all supported units (from kB to TB and KiB to TiB)
+	supported_units := []struct {
+		re       *regexp.Regexp
+		multiple uint64
+	}{
+		{regexp.MustCompile(`^\s*[[:digit:]]+\s*kB$`), KiloByte},
+		{regexp.MustCompile(`^\s*[[:digit:]]+\s*KiB$`), KibiByte},
+		{regexp.MustCompile(`^\s*[[:digit:]]+\s*MB$`), MegaByte},
+		{regexp.MustCompile(`^\s*[[:digit:]]+\s*MiB$`), MebiByte},
+		{regexp.MustCompile(`^\s*[[:digit:]]+\s*GB$`), GigaByte},
+		{regexp.MustCompile(`^\s*[[:digit:]]+\s*GiB$`), GibiByte},
+		{regexp.MustCompile(`^\s*[[:digit:]]+\s*TB$`), TeraByte},
+		{regexp.MustCompile(`^\s*[[:digit:]]+\s*TiB$`), TebiByte},
+		{regexp.MustCompile(`^\s*[[:digit:]]+$`), 1},
+	}
+
+	for _, unit := range supported_units {
+		if unit.re.MatchString(size) {
+			return_size *= unit.multiple
+			return return_size, nil
+		}
+	}
+
+	// In case the strign didn't match any of the above regexes, return nil
+	// even if a number was found. This is to prevent users from submitting
+	// unknown units.
+	return 0, fmt.Errorf("unknown data size units in string: %s", size)
+}
+
+// NopSeekCloser returns an io.ReadSeekCloser with a no-op Close method
+// wrapping the provided io.ReadSeeker r.
+func NopSeekCloser(r io.ReadSeeker) io.ReadSeekCloser {
+	return nopSeekCloser{r}
+}
+
+type nopSeekCloser struct {
+	io.ReadSeeker
+}
+
+func (nopSeekCloser) Close() error { return nil }