first commit
diff --git a/updater/install.c b/updater/install.c
new file mode 100644
index 0000000..d23ec64
--- /dev/null
+++ b/updater/install.c
@@ -0,0 +1,1039 @@
+/*
+ * Copyright (C) 2009 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#include <ctype.h>
+#include <errno.h>
+#include <stdarg.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <sys/mount.h>
+#include <sys/stat.h>
+#include <sys/types.h>
+#include <sys/wait.h>
+#include <unistd.h>
+
+#include "cutils/misc.h"
+#include "cutils/properties.h"
+#include "edify/expr.h"
+#include "mincrypt/sha.h"
+#include "minzip/DirUtil.h"
+#include "mounts.h"
+#include "mtdutils/mtdutils.h"
+#include "updater.h"
+#include "applypatch/applypatch.h"
+
+#ifdef USE_EXT4
+#include "make_ext4fs.h"
+#endif
+
+// mount(fs_type, partition_type, location, mount_point)
+//
+//    fs_type="yaffs2" partition_type="MTD"     location=partition
+//    fs_type="ext4"   partition_type="EMMC"    location=device
+Value* MountFn(const char* name, State* state, int argc, Expr* argv[]) {
+    char* result = NULL;
+    if (argc != 4) {
+        return ErrorAbort(state, "%s() expects 4 args, got %d", name, argc);
+    }
+    char* fs_type;
+    char* partition_type;
+    char* location;
+    char* mount_point;
+    if (ReadArgs(state, argv, 4, &fs_type, &partition_type,
+                 &location, &mount_point) < 0) {
+        return NULL;
+    }
+
+    if (strlen(fs_type) == 0) {
+        ErrorAbort(state, "fs_type argument to %s() can't be empty", name);
+        goto done;
+    }
+    if (strlen(partition_type) == 0) {
+        ErrorAbort(state, "partition_type argument to %s() can't be empty",
+                   name);
+        goto done;
+    }
+    if (strlen(location) == 0) {
+        ErrorAbort(state, "location argument to %s() can't be empty", name);
+        goto done;
+    }
+    if (strlen(mount_point) == 0) {
+        ErrorAbort(state, "mount_point argument to %s() can't be empty", name);
+        goto done;
+    }
+
+    mkdir(mount_point, 0755);
+
+    if (strcmp(partition_type, "MTD") == 0) {
+        mtd_scan_partitions();
+        const MtdPartition* mtd;
+        mtd = mtd_find_partition_by_name(location);
+        if (mtd == NULL) {
+            fprintf(stderr, "%s: no mtd partition named \"%s\"",
+                    name, location);
+            result = strdup("");
+            goto done;
+        }
+        if (mtd_mount_partition(mtd, mount_point, fs_type, 0 /* rw */) != 0) {
+            fprintf(stderr, "mtd mount of %s failed: %s\n",
+                    location, strerror(errno));
+            result = strdup("");
+            goto done;
+        }
+        result = mount_point;
+    } else {
+        if (mount(location, mount_point, fs_type,
+                  MS_NOATIME | MS_NODEV | MS_NODIRATIME, "") < 0) {
+            fprintf(stderr, "%s: failed to mount %s at %s: %s\n",
+                    name, location, mount_point, strerror(errno));
+            result = strdup("");
+        } else {
+            result = mount_point;
+        }
+    }
+
+done:
+    free(fs_type);
+    free(partition_type);
+    free(location);
+    if (result != mount_point) free(mount_point);
+    return StringValue(result);
+}
+
+
+// is_mounted(mount_point)
+Value* IsMountedFn(const char* name, State* state, int argc, Expr* argv[]) {
+    char* result = NULL;
+    if (argc != 1) {
+        return ErrorAbort(state, "%s() expects 1 arg, got %d", name, argc);
+    }
+    char* mount_point;
+    if (ReadArgs(state, argv, 1, &mount_point) < 0) {
+        return NULL;
+    }
+    if (strlen(mount_point) == 0) {
+        ErrorAbort(state, "mount_point argument to unmount() can't be empty");
+        goto done;
+    }
+
+    scan_mounted_volumes();
+    const MountedVolume* vol = find_mounted_volume_by_mount_point(mount_point);
+    if (vol == NULL) {
+        result = strdup("");
+    } else {
+        result = mount_point;
+    }
+
+done:
+    if (result != mount_point) free(mount_point);
+    return StringValue(result);
+}
+
+
+Value* UnmountFn(const char* name, State* state, int argc, Expr* argv[]) {
+    char* result = NULL;
+    if (argc != 1) {
+        return ErrorAbort(state, "%s() expects 1 arg, got %d", name, argc);
+    }
+    char* mount_point;
+    if (ReadArgs(state, argv, 1, &mount_point) < 0) {
+        return NULL;
+    }
+    if (strlen(mount_point) == 0) {
+        ErrorAbort(state, "mount_point argument to unmount() can't be empty");
+        goto done;
+    }
+
+    scan_mounted_volumes();
+    const MountedVolume* vol = find_mounted_volume_by_mount_point(mount_point);
+    if (vol == NULL) {
+        fprintf(stderr, "unmount of %s failed; no such volume\n", mount_point);
+        result = strdup("");
+    } else {
+        unmount_mounted_volume(vol);
+        result = mount_point;
+    }
+
+done:
+    if (result != mount_point) free(mount_point);
+    return StringValue(result);
+}
+
+
+// format(fs_type, partition_type, location)
+//
+//    fs_type="yaffs2" partition_type="MTD"     location=partition
+//    fs_type="ext4"   partition_type="EMMC"    location=device
+Value* FormatFn(const char* name, State* state, int argc, Expr* argv[]) {
+    char* result = NULL;
+    if (argc != 3) {
+        return ErrorAbort(state, "%s() expects 3 args, got %d", name, argc);
+    }
+    char* fs_type;
+    char* partition_type;
+    char* location;
+    if (ReadArgs(state, argv, 3, &fs_type, &partition_type, &location) < 0) {
+        return NULL;
+    }
+
+    if (strlen(fs_type) == 0) {
+        ErrorAbort(state, "fs_type argument to %s() can't be empty", name);
+        goto done;
+    }
+    if (strlen(partition_type) == 0) {
+        ErrorAbort(state, "partition_type argument to %s() can't be empty",
+                   name);
+        goto done;
+    }
+    if (strlen(location) == 0) {
+        ErrorAbort(state, "location argument to %s() can't be empty", name);
+        goto done;
+    }
+
+    if (strcmp(partition_type, "MTD") == 0) {
+        mtd_scan_partitions();
+        const MtdPartition* mtd = mtd_find_partition_by_name(location);
+        if (mtd == NULL) {
+            fprintf(stderr, "%s: no mtd partition named \"%s\"",
+                    name, location);
+            result = strdup("");
+            goto done;
+        }
+        MtdWriteContext* ctx = mtd_write_partition(mtd);
+        if (ctx == NULL) {
+            fprintf(stderr, "%s: can't write \"%s\"", name, location);
+            result = strdup("");
+            goto done;
+        }
+        if (mtd_erase_blocks(ctx, -1) == -1) {
+            mtd_write_close(ctx);
+            fprintf(stderr, "%s: failed to erase \"%s\"", name, location);
+            result = strdup("");
+            goto done;
+        }
+        if (mtd_write_close(ctx) != 0) {
+            fprintf(stderr, "%s: failed to close \"%s\"", name, location);
+            result = strdup("");
+            goto done;
+        }
+        result = location;
+#ifdef USE_EXT4
+    } else if (strcmp(fs_type, "ext4") == 0) {
+        reset_ext4fs_info();
+        int status = make_ext4fs(location, NULL, NULL, 0, 0, 0);
+        if (status != 0) {
+            fprintf(stderr, "%s: make_ext4fs failed (%d) on %s",
+                    name, status, location);
+            result = strdup("");
+            goto done;
+        }
+        result = location;
+#endif
+    } else if (strcmp(fs_type, "ext2") == 0) {
+        int status = format_ext2_device(location);
+        if (status != 0) {
+            fprintf(stderr, "%s: format_ext2_device failed (%d) on %s",
+                    name, status, location);
+            result = strdup("");
+            goto done;
+        }
+        result = location;
+    } else if (strcmp(fs_type, "ext3") == 0) {
+        int status = format_ext3_device(location);
+        if (status != 0) {
+            fprintf(stderr, "%s: format_ext3_device failed (%d) on %s",
+                    name, status, location);
+            result = strdup("");
+            goto done;
+        }
+        result = location;
+    } else {
+        fprintf(stderr, "%s: unsupported fs_type \"%s\" partition_type \"%s\"",
+                name, fs_type, partition_type);
+    }
+
+done:
+    free(fs_type);
+    free(partition_type);
+    if (result != location) free(location);
+    return StringValue(result);
+}
+
+
+Value* DeleteFn(const char* name, State* state, int argc, Expr* argv[]) {
+    char** paths = malloc(argc * sizeof(char*));
+    int i;
+    for (i = 0; i < argc; ++i) {
+        paths[i] = Evaluate(state, argv[i]);
+        if (paths[i] == NULL) {
+            int j;
+            for (j = 0; j < i; ++i) {
+                free(paths[j]);
+            }
+            free(paths);
+            return NULL;
+        }
+    }
+
+    bool recursive = (strcmp(name, "delete_recursive") == 0);
+
+    int success = 0;
+    for (i = 0; i < argc; ++i) {
+        if ((recursive ? dirUnlinkHierarchy(paths[i]) : unlink(paths[i])) == 0)
+            ++success;
+        free(paths[i]);
+    }
+    free(paths);
+
+    char buffer[10];
+    sprintf(buffer, "%d", success);
+    return StringValue(strdup(buffer));
+}
+
+
+Value* ShowProgressFn(const char* name, State* state, int argc, Expr* argv[]) {
+    if (argc != 2) {
+        return ErrorAbort(state, "%s() expects 2 args, got %d", name, argc);
+    }
+    char* frac_str;
+    char* sec_str;
+    if (ReadArgs(state, argv, 2, &frac_str, &sec_str) < 0) {
+        return NULL;
+    }
+
+    double frac = strtod(frac_str, NULL);
+    int sec = strtol(sec_str, NULL, 10);
+
+    UpdaterInfo* ui = (UpdaterInfo*)(state->cookie);
+    fprintf(ui->cmd_pipe, "progress %f %d\n", frac, sec);
+
+    free(sec_str);
+    return StringValue(frac_str);
+}
+
+Value* SetProgressFn(const char* name, State* state, int argc, Expr* argv[]) {
+    if (argc != 1) {
+        return ErrorAbort(state, "%s() expects 1 arg, got %d", name, argc);
+    }
+    char* frac_str;
+    if (ReadArgs(state, argv, 1, &frac_str) < 0) {
+        return NULL;
+    }
+
+    double frac = strtod(frac_str, NULL);
+
+    UpdaterInfo* ui = (UpdaterInfo*)(state->cookie);
+    fprintf(ui->cmd_pipe, "set_progress %f\n", frac);
+
+    return StringValue(frac_str);
+}
+
+// package_extract_dir(package_path, destination_path)
+Value* PackageExtractDirFn(const char* name, State* state,
+                          int argc, Expr* argv[]) {
+    if (argc != 2) {
+        return ErrorAbort(state, "%s() expects 2 args, got %d", name, argc);
+    }
+    char* zip_path;
+    char* dest_path;
+    if (ReadArgs(state, argv, 2, &zip_path, &dest_path) < 0) return NULL;
+
+    ZipArchive* za = ((UpdaterInfo*)(state->cookie))->package_zip;
+
+    // To create a consistent system image, never use the clock for timestamps.
+    struct utimbuf timestamp = { 1217592000, 1217592000 };  // 8/1/2008 default
+
+    bool success = mzExtractRecursive(za, zip_path, dest_path,
+                                      MZ_EXTRACT_FILES_ONLY, &timestamp,
+                                      NULL, NULL);
+    free(zip_path);
+    free(dest_path);
+    return StringValue(strdup(success ? "t" : ""));
+}
+
+
+// package_extract_file(package_path, destination_path)
+//   or
+// package_extract_file(package_path)
+//   to return the entire contents of the file as the result of this
+//   function (the char* returned is actually a FileContents*).
+Value* PackageExtractFileFn(const char* name, State* state,
+                           int argc, Expr* argv[]) {
+    if (argc != 1 && argc != 2) {
+        return ErrorAbort(state, "%s() expects 1 or 2 args, got %d",
+                          name, argc);
+    }
+    bool success = false;
+    if (argc == 2) {
+        // The two-argument version extracts to a file.
+
+        char* zip_path;
+        char* dest_path;
+        if (ReadArgs(state, argv, 2, &zip_path, &dest_path) < 0) return NULL;
+
+        ZipArchive* za = ((UpdaterInfo*)(state->cookie))->package_zip;
+        const ZipEntry* entry = mzFindZipEntry(za, zip_path);
+        if (entry == NULL) {
+            fprintf(stderr, "%s: no %s in package\n", name, zip_path);
+            goto done2;
+        }
+
+        FILE* f = fopen(dest_path, "wb");
+        if (f == NULL) {
+            fprintf(stderr, "%s: can't open %s for write: %s\n",
+                    name, dest_path, strerror(errno));
+            goto done2;
+        }
+        success = mzExtractZipEntryToFile(za, entry, fileno(f));
+        fclose(f);
+
+      done2:
+        free(zip_path);
+        free(dest_path);
+        return StringValue(strdup(success ? "t" : ""));
+    } else {
+        // The one-argument version returns the contents of the file
+        // as the result.
+
+        char* zip_path;
+        Value* v = malloc(sizeof(Value));
+        v->type = VAL_BLOB;
+        v->size = -1;
+        v->data = NULL;
+
+        if (ReadArgs(state, argv, 1, &zip_path) < 0) return NULL;
+
+        ZipArchive* za = ((UpdaterInfo*)(state->cookie))->package_zip;
+        const ZipEntry* entry = mzFindZipEntry(za, zip_path);
+        if (entry == NULL) {
+            fprintf(stderr, "%s: no %s in package\n", name, zip_path);
+            goto done1;
+        }
+
+        v->size = mzGetZipEntryUncompLen(entry);
+        v->data = malloc(v->size);
+        if (v->data == NULL) {
+            fprintf(stderr, "%s: failed to allocate %ld bytes for %s\n",
+                    name, (long)v->size, zip_path);
+            goto done1;
+        }
+
+        success = mzExtractZipEntryToBuffer(za, entry,
+                                            (unsigned char *)v->data);
+
+      done1:
+        free(zip_path);
+        if (!success) {
+            free(v->data);
+            v->data = NULL;
+            v->size = -1;
+        }
+        return v;
+    }
+}
+
+
+// symlink target src1 src2 ...
+//    unlinks any previously existing src1, src2, etc before creating symlinks.
+Value* SymlinkFn(const char* name, State* state, int argc, Expr* argv[]) {
+    if (argc == 0) {
+        return ErrorAbort(state, "%s() expects 1+ args, got %d", name, argc);
+    }
+    char* target;
+    target = Evaluate(state, argv[0]);
+    if (target == NULL) return NULL;
+
+    char** srcs = ReadVarArgs(state, argc-1, argv+1);
+    if (srcs == NULL) {
+        free(target);
+        return NULL;
+    }
+
+    int i;
+    for (i = 0; i < argc-1; ++i) {
+        if (unlink(srcs[i]) < 0) {
+            if (errno != ENOENT) {
+                fprintf(stderr, "%s: failed to remove %s: %s\n",
+                        name, srcs[i], strerror(errno));
+            }
+        }
+        if (symlink(target, srcs[i]) < 0) {
+            fprintf(stderr, "%s: failed to symlink %s to %s: %s\n",
+                    name, srcs[i], target, strerror(errno));
+        }
+        free(srcs[i]);
+    }
+    free(srcs);
+    return StringValue(strdup(""));
+}
+
+
+Value* SetPermFn(const char* name, State* state, int argc, Expr* argv[]) {
+    char* result = NULL;
+    bool recursive = (strcmp(name, "set_perm_recursive") == 0);
+
+    int min_args = 4 + (recursive ? 1 : 0);
+    if (argc < min_args) {
+        return ErrorAbort(state, "%s() expects %d+ args, got %d", name, argc);
+    }
+
+    char** args = ReadVarArgs(state, argc, argv);
+    if (args == NULL) return NULL;
+
+    char* end;
+    int i;
+
+    int uid = strtoul(args[0], &end, 0);
+    if (*end != '\0' || args[0][0] == 0) {
+        ErrorAbort(state, "%s: \"%s\" not a valid uid", name, args[0]);
+        goto done;
+    }
+
+    int gid = strtoul(args[1], &end, 0);
+    if (*end != '\0' || args[1][0] == 0) {
+        ErrorAbort(state, "%s: \"%s\" not a valid gid", name, args[1]);
+        goto done;
+    }
+
+    if (recursive) {
+        int dir_mode = strtoul(args[2], &end, 0);
+        if (*end != '\0' || args[2][0] == 0) {
+            ErrorAbort(state, "%s: \"%s\" not a valid dirmode", name, args[2]);
+            goto done;
+        }
+
+        int file_mode = strtoul(args[3], &end, 0);
+        if (*end != '\0' || args[3][0] == 0) {
+            ErrorAbort(state, "%s: \"%s\" not a valid filemode",
+                       name, args[3]);
+            goto done;
+        }
+
+        for (i = 4; i < argc; ++i) {
+            dirSetHierarchyPermissions(args[i], uid, gid, dir_mode, file_mode);
+        }
+    } else {
+        int mode = strtoul(args[2], &end, 0);
+        if (*end != '\0' || args[2][0] == 0) {
+            ErrorAbort(state, "%s: \"%s\" not a valid mode", name, args[2]);
+            goto done;
+        }
+
+        for (i = 3; i < argc; ++i) {
+            if (chown(args[i], uid, gid) < 0) {
+                fprintf(stderr, "%s: chown of %s to %d %d failed: %s\n",
+                        name, args[i], uid, gid, strerror(errno));
+            }
+            if (chmod(args[i], mode) < 0) {
+                fprintf(stderr, "%s: chmod of %s to %o failed: %s\n",
+                        name, args[i], mode, strerror(errno));
+            }
+        }
+    }
+    result = strdup("");
+
+done:
+    for (i = 0; i < argc; ++i) {
+        free(args[i]);
+    }
+    free(args);
+
+    return StringValue(result);
+}
+
+
+Value* GetPropFn(const char* name, State* state, int argc, Expr* argv[]) {
+    if (argc != 1) {
+        return ErrorAbort(state, "%s() expects 1 arg, got %d", name, argc);
+    }
+    char* key;
+    key = Evaluate(state, argv[0]);
+    if (key == NULL) return NULL;
+
+    char value[PROPERTY_VALUE_MAX];
+    property_get(key, value, "");
+    free(key);
+
+    return StringValue(strdup(value));
+}
+
+
+// file_getprop(file, key)
+//
+//   interprets 'file' as a getprop-style file (key=value pairs, one
+//   per line, # comment lines and blank lines okay), and returns the value
+//   for 'key' (or "" if it isn't defined).
+Value* FileGetPropFn(const char* name, State* state, int argc, Expr* argv[]) {
+    char* result = NULL;
+    char* buffer = NULL;
+    char* filename;
+    char* key;
+    if (ReadArgs(state, argv, 2, &filename, &key) < 0) {
+        return NULL;
+    }
+
+    struct stat st;
+    if (stat(filename, &st) < 0) {
+        ErrorAbort(state, "%s: failed to stat \"%s\": %s",
+                   name, filename, strerror(errno));
+        goto done;
+    }
+
+#define MAX_FILE_GETPROP_SIZE    65536
+
+    if (st.st_size > MAX_FILE_GETPROP_SIZE) {
+        ErrorAbort(state, "%s too large for %s (max %d)",
+                   filename, name, MAX_FILE_GETPROP_SIZE);
+        goto done;
+    }
+
+    buffer = malloc(st.st_size+1);
+    if (buffer == NULL) {
+        ErrorAbort(state, "%s: failed to alloc %d bytes", name, st.st_size+1);
+        goto done;
+    }
+
+    FILE* f = fopen(filename, "rb");
+    if (f == NULL) {
+        ErrorAbort(state, "%s: failed to open %s: %s",
+                   name, filename, strerror(errno));
+        goto done;
+    }
+
+    if (fread(buffer, 1, st.st_size, f) != st.st_size) {
+        ErrorAbort(state, "%s: failed to read %d bytes from %s",
+                   name, st.st_size+1, filename);
+        fclose(f);
+        goto done;
+    }
+    buffer[st.st_size] = '\0';
+
+    fclose(f);
+
+    char* line = strtok(buffer, "\n");
+    do {
+        // skip whitespace at start of line
+        while (*line && isspace(*line)) ++line;
+
+        // comment or blank line: skip to next line
+        if (*line == '\0' || *line == '#') continue;
+
+        char* equal = strchr(line, '=');
+        if (equal == NULL) {
+            ErrorAbort(state, "%s: malformed line \"%s\": %s not a prop file?",
+                       name, line, filename);
+            goto done;
+        }
+
+        // trim whitespace between key and '='
+        char* key_end = equal-1;
+        while (key_end > line && isspace(*key_end)) --key_end;
+        key_end[1] = '\0';
+
+        // not the key we're looking for
+        if (strcmp(key, line) != 0) continue;
+
+        // skip whitespace after the '=' to the start of the value
+        char* val_start = equal+1;
+        while(*val_start && isspace(*val_start)) ++val_start;
+
+        // trim trailing whitespace
+        char* val_end = val_start + strlen(val_start)-1;
+        while (val_end > val_start && isspace(*val_end)) --val_end;
+        val_end[1] = '\0';
+
+        result = strdup(val_start);
+        break;
+
+    } while ((line = strtok(NULL, "\n")));
+
+    if (result == NULL) result = strdup("");
+
+  done:
+    free(filename);
+    free(key);
+    free(buffer);
+    return StringValue(result);
+}
+
+
+static bool write_raw_image_cb(const unsigned char* data,
+                               int data_len, void* ctx) {
+    int r = mtd_write_data((MtdWriteContext*)ctx, (const char *)data, data_len);
+    if (r == data_len) return true;
+    fprintf(stderr, "%s\n", strerror(errno));
+    return false;
+}
+
+// write_raw_image(file, partition)
+Value* WriteRawImageFn(const char* name, State* state, int argc, Expr* argv[]) {
+    char* result = NULL;
+
+    char* partition;
+    char* filename;
+    if (ReadArgs(state, argv, 2, &filename, &partition) < 0) {
+        return NULL;
+    }
+
+    if (strlen(partition) == 0) {
+        ErrorAbort(state, "partition argument to %s can't be empty", name);
+        goto done;
+    }
+    if (strlen(filename) == 0) {
+        ErrorAbort(state, "file argument to %s can't be empty", name);
+        goto done;
+    }
+
+    if (0 == restore_raw_partition(partition, filename))
+        result = strdup(partition);
+    else
+        result = strdup("");
+
+done:
+    if (result != partition) free(partition);
+    free(filename);
+    return StringValue(result);
+}
+
+// apply_patch_space(bytes)
+Value* ApplyPatchSpaceFn(const char* name, State* state,
+                         int argc, Expr* argv[]) {
+    char* bytes_str;
+    if (ReadArgs(state, argv, 1, &bytes_str) < 0) {
+        return NULL;
+    }
+
+    char* endptr;
+    size_t bytes = strtol(bytes_str, &endptr, 10);
+    if (bytes == 0 && endptr == bytes_str) {
+        ErrorAbort(state, "%s(): can't parse \"%s\" as byte count\n\n",
+                   name, bytes_str);
+        free(bytes_str);
+        return NULL;
+    }
+
+    return StringValue(strdup(CacheSizeCheck(bytes) ? "" : "t"));
+}
+
+
+// apply_patch(srcfile, tgtfile, tgtsha1, tgtsize, sha1_1, patch_1, ...)
+Value* ApplyPatchFn(const char* name, State* state, int argc, Expr* argv[]) {
+    if (argc < 6 || (argc % 2) == 1) {
+        return ErrorAbort(state, "%s(): expected at least 6 args and an "
+                                 "even number, got %d",
+                          name, argc);
+    }
+
+    char* source_filename;
+    char* target_filename;
+    char* target_sha1;
+    char* target_size_str;
+    if (ReadArgs(state, argv, 4, &source_filename, &target_filename,
+                 &target_sha1, &target_size_str) < 0) {
+        return NULL;
+    }
+
+    char* endptr;
+    size_t target_size = strtol(target_size_str, &endptr, 10);
+    if (target_size == 0 && endptr == target_size_str) {
+        ErrorAbort(state, "%s(): can't parse \"%s\" as byte count",
+                   name, target_size_str);
+        free(source_filename);
+        free(target_filename);
+        free(target_sha1);
+        free(target_size_str);
+        return NULL;
+    }
+
+    int patchcount = (argc-4) / 2;
+    Value** patches = ReadValueVarArgs(state, argc-4, argv+4);
+
+    int i;
+    for (i = 0; i < patchcount; ++i) {
+        if (patches[i*2]->type != VAL_STRING) {
+            ErrorAbort(state, "%s(): sha-1 #%d is not string", name, i);
+            break;
+        }
+        if (patches[i*2+1]->type != VAL_BLOB) {
+            ErrorAbort(state, "%s(): patch #%d is not blob", name, i);
+            break;
+        }
+    }
+    if (i != patchcount) {
+        for (i = 0; i < patchcount*2; ++i) {
+            FreeValue(patches[i]);
+        }
+        free(patches);
+        return NULL;
+    }
+
+    char** patch_sha_str = malloc(patchcount * sizeof(char*));
+    for (i = 0; i < patchcount; ++i) {
+        patch_sha_str[i] = patches[i*2]->data;
+        patches[i*2]->data = NULL;
+        FreeValue(patches[i*2]);
+        patches[i] = patches[i*2+1];
+    }
+
+    int result = applypatch(source_filename, target_filename,
+                            target_sha1, target_size,
+                            patchcount, patch_sha_str, patches);
+
+    for (i = 0; i < patchcount; ++i) {
+        FreeValue(patches[i]);
+    }
+    free(patch_sha_str);
+    free(patches);
+
+    return StringValue(strdup(result == 0 ? "t" : ""));
+}
+
+// apply_patch_check(file, [sha1_1, ...])
+Value* ApplyPatchCheckFn(const char* name, State* state,
+                         int argc, Expr* argv[]) {
+    if (argc < 1) {
+        return ErrorAbort(state, "%s(): expected at least 1 arg, got %d",
+                          name, argc);
+    }
+
+    char* filename;
+    if (ReadArgs(state, argv, 1, &filename) < 0) {
+        return NULL;
+    }
+
+    int patchcount = argc-1;
+    char** sha1s = ReadVarArgs(state, argc-1, argv+1);
+
+    int result = applypatch_check(filename, patchcount, sha1s);
+
+    int i;
+    for (i = 0; i < patchcount; ++i) {
+        free(sha1s[i]);
+    }
+    free(sha1s);
+
+    return StringValue(strdup(result == 0 ? "t" : ""));
+}
+
+Value* UIPrintFn(const char* name, State* state, int argc, Expr* argv[]) {
+    char** args = ReadVarArgs(state, argc, argv);
+    if (args == NULL) {
+        return NULL;
+    }
+
+    int size = 0;
+    int i;
+    for (i = 0; i < argc; ++i) {
+        size += strlen(args[i]);
+    }
+    char* buffer = malloc(size+1);
+    size = 0;
+    for (i = 0; i < argc; ++i) {
+        strcpy(buffer+size, args[i]);
+        size += strlen(args[i]);
+        free(args[i]);
+    }
+    free(args);
+    buffer[size] = '\0';
+
+    char* line = strtok(buffer, "\n");
+    while (line) {
+        fprintf(((UpdaterInfo*)(state->cookie))->cmd_pipe,
+                "ui_print %s\n", line);
+        line = strtok(NULL, "\n");
+    }
+    fprintf(((UpdaterInfo*)(state->cookie))->cmd_pipe, "ui_print\n");
+
+    return StringValue(buffer);
+}
+
+Value* RunProgramFn(const char* name, State* state, int argc, Expr* argv[]) {
+    if (argc < 1) {
+        return ErrorAbort(state, "%s() expects at least 1 arg", name);
+    }
+    char** args = ReadVarArgs(state, argc, argv);
+    if (args == NULL) {
+        return NULL;
+    }
+
+    char** args2 = malloc(sizeof(char*) * (argc+1));
+    memcpy(args2, args, sizeof(char*) * argc);
+    args2[argc] = NULL;
+
+    fprintf(stderr, "about to run program [%s] with %d args\n", args2[0], argc);
+
+    pid_t child = fork();
+    if (child == 0) {
+        execv(args2[0], args2);
+        fprintf(stderr, "run_program: execv failed: %s\n", strerror(errno));
+        _exit(1);
+    }
+    int status;
+    waitpid(child, &status, 0);
+    if (WIFEXITED(status)) {
+        if (WEXITSTATUS(status) != 0) {
+            fprintf(stderr, "run_program: child exited with status %d\n",
+                    WEXITSTATUS(status));
+        }
+    } else if (WIFSIGNALED(status)) {
+        fprintf(stderr, "run_program: child terminated by signal %d\n",
+                WTERMSIG(status));
+    }
+
+    int i;
+    for (i = 0; i < argc; ++i) {
+        free(args[i]);
+    }
+    free(args);
+    free(args2);
+
+    char buffer[20];
+    sprintf(buffer, "%d", status);
+
+    return StringValue(strdup(buffer));
+}
+
+// Take a sha-1 digest and return it as a newly-allocated hex string.
+static char* PrintSha1(uint8_t* digest) {
+    char* buffer = malloc(SHA_DIGEST_SIZE*2 + 1);
+    int i;
+    const char* alphabet = "0123456789abcdef";
+    for (i = 0; i < SHA_DIGEST_SIZE; ++i) {
+        buffer[i*2] = alphabet[(digest[i] >> 4) & 0xf];
+        buffer[i*2+1] = alphabet[digest[i] & 0xf];
+    }
+    buffer[i*2] = '\0';
+    return buffer;
+}
+
+// sha1_check(data)
+//    to return the sha1 of the data (given in the format returned by
+//    read_file).
+//
+// sha1_check(data, sha1_hex, [sha1_hex, ...])
+//    returns the sha1 of the file if it matches any of the hex
+//    strings passed, or "" if it does not equal any of them.
+//
+Value* Sha1CheckFn(const char* name, State* state, int argc, Expr* argv[]) {
+    if (argc < 1) {
+        return ErrorAbort(state, "%s() expects at least 1 arg", name);
+    }
+
+    Value** args = ReadValueVarArgs(state, argc, argv);
+    if (args == NULL) {
+        return NULL;
+    }
+
+    if (args[0]->size < 0) {
+        fprintf(stderr, "%s(): no file contents received", name);
+        return StringValue(strdup(""));
+    }
+    uint8_t digest[SHA_DIGEST_SIZE];
+    SHA(args[0]->data, args[0]->size, digest);
+    FreeValue(args[0]);
+
+    if (argc == 1) {
+        return StringValue(PrintSha1(digest));
+    }
+
+    int i;
+    uint8_t* arg_digest = malloc(SHA_DIGEST_SIZE);
+    for (i = 1; i < argc; ++i) {
+        if (args[i]->type != VAL_STRING) {
+            fprintf(stderr, "%s(): arg %d is not a string; skipping",
+                    name, i);
+        } else if (ParseSha1(args[i]->data, arg_digest) != 0) {
+            // Warn about bad args and skip them.
+            fprintf(stderr, "%s(): error parsing \"%s\" as sha-1; skipping",
+                    name, args[i]->data);
+        } else if (memcmp(digest, arg_digest, SHA_DIGEST_SIZE) == 0) {
+            break;
+        }
+        FreeValue(args[i]);
+    }
+    if (i >= argc) {
+        // Didn't match any of the hex strings; return false.
+        return StringValue(strdup(""));
+    }
+    // Found a match; free all the remaining arguments and return the
+    // matched one.
+    int j;
+    for (j = i+1; j < argc; ++j) {
+        FreeValue(args[j]);
+    }
+    return args[i];
+}
+
+// Read a local file and return its contents (the char* returned
+// is actually a FileContents*).
+Value* ReadFileFn(const char* name, State* state, int argc, Expr* argv[]) {
+    if (argc != 1) {
+        return ErrorAbort(state, "%s() expects 1 arg, got %d", name, argc);
+    }
+    char* filename;
+    if (ReadArgs(state, argv, 1, &filename) < 0) return NULL;
+
+    Value* v = malloc(sizeof(Value));
+    v->type = VAL_BLOB;
+
+    FileContents fc;
+    if (LoadFileContents(filename, &fc) != 0) {
+        ErrorAbort(state, "%s() loading \"%s\" failed: %s",
+                   name, filename, strerror(errno));
+        free(filename);
+        free(v);
+        free(fc.data);
+        return NULL;
+    }
+
+    v->size = fc.size;
+    v->data = (char*)fc.data;
+
+    free(filename);
+    return v;
+}
+
+void RegisterInstallFunctions() {
+    RegisterFunction("mount", MountFn);
+    RegisterFunction("is_mounted", IsMountedFn);
+    RegisterFunction("unmount", UnmountFn);
+    RegisterFunction("format", FormatFn);
+    RegisterFunction("show_progress", ShowProgressFn);
+    RegisterFunction("set_progress", SetProgressFn);
+    RegisterFunction("delete", DeleteFn);
+    RegisterFunction("delete_recursive", DeleteFn);
+    RegisterFunction("package_extract_dir", PackageExtractDirFn);
+    RegisterFunction("package_extract_file", PackageExtractFileFn);
+    RegisterFunction("symlink", SymlinkFn);
+    RegisterFunction("set_perm", SetPermFn);
+    RegisterFunction("set_perm_recursive", SetPermFn);
+
+    RegisterFunction("getprop", GetPropFn);
+    RegisterFunction("file_getprop", FileGetPropFn);
+    RegisterFunction("write_raw_image", WriteRawImageFn);
+
+    RegisterFunction("apply_patch", ApplyPatchFn);
+    RegisterFunction("apply_patch_check", ApplyPatchCheckFn);
+    RegisterFunction("apply_patch_space", ApplyPatchSpaceFn);
+
+    RegisterFunction("read_file", ReadFileFn);
+    RegisterFunction("sha1_check", Sha1CheckFn);
+
+    RegisterFunction("ui_print", UIPrintFn);
+
+    RegisterFunction("run_program", RunProgramFn);
+}