updater.c revision 779701db515d1a0d363d5a8896252f331bc4e22a 
1/*
2 * Copyright (C) 2009 The Android Open Source Project
3 *
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
7 *
8 *      http://www.apache.org/licenses/LICENSE-2.0
9 *
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
15 */
16
17#include <stdio.h>
18#include <unistd.h>
19#include <stdlib.h>
20
21#include "edify/expr.h"
22#include "updater.h"
23#include "install.h"
24#include "minzip/Zip.h"
25
26// Generated by the makefile, this function defines the
27// RegisterDeviceExtensions() function, which calls all the
28// registration functions for device-specific extensions.
29#include "register.inc"
30
31// Where in the package we expect to find the edify script to execute.
32// (Note it's "updateR-script", not the older "update-script".)
33#define SCRIPT_NAME "META-INF/com/google/android/updater-script"
34
35struct selabel_handle *sehandle;
36
37int main(int argc, char** argv) {
38    // Various things log information to stdout or stderr more or less
39    // at random.  The log file makes more sense if buffering is
40    // turned off so things appear in the right order.
41    setbuf(stdout, NULL);
42    setbuf(stderr, NULL);
43
44    if (argc != 4) {
45        fprintf(stderr, "unexpected number of arguments (%d)\n", argc);
46        return 1;
47    }
48
49    char* version = argv[1];
50    if ((version[0] != '1' && version[0] != '2' && version[0] != '3') ||
51        version[1] != '\0') {
52        // We support version 1, 2, or 3.
53        fprintf(stderr, "wrong updater binary API; expected 1, 2, or 3; "
54                        "got %s\n",
55                argv[1]);
56        return 2;
57    }
58
59    // Set up the pipe for sending commands back to the parent process.
60
61    int fd = atoi(argv[2]);
62    FILE* cmd_pipe = fdopen(fd, "wb");
63    setlinebuf(cmd_pipe);
64
65    // Extract the script from the package.
66
67    char* package_data = argv[3];
68    ZipArchive za;
69    int err;
70    err = mzOpenZipArchive(package_data, &za);
71    if (err != 0) {
72        fprintf(stderr, "failed to open package %s: %s\n",
73                package_data, strerror(err));
74        return 3;
75    }
76
77    const ZipEntry* script_entry = mzFindZipEntry(&za, SCRIPT_NAME);
78    if (script_entry == NULL) {
79        fprintf(stderr, "failed to find %s in %s\n", SCRIPT_NAME, package_data);
80        return 4;
81    }
82
83    char* script = malloc(script_entry->uncompLen+1);
84    if (!mzReadZipEntry(&za, script_entry, script, script_entry->uncompLen)) {
85        fprintf(stderr, "failed to read script from package\n");
86        return 5;
87    }
88    script[script_entry->uncompLen] = '\0';
89
90    // Configure edify's functions.
91
92    RegisterBuiltins();
93    RegisterInstallFunctions();
94    RegisterDeviceExtensions();
95    FinishRegistration();
96
97    // Parse the script.
98
99    Expr* root;
100    int error_count = 0;
101    yy_scan_string(script);
102    int error = yyparse(&root, &error_count);
103    if (error != 0 || error_count > 0) {
104        fprintf(stderr, "%d parse errors\n", error_count);
105        return 6;
106    }
107
108#ifdef HAVE_SELINUX
109    struct selinux_opt seopts[] = {
110      { SELABEL_OPT_PATH, "/file_contexts" }
111    };
112
113    sehandle = selabel_open(SELABEL_CTX_FILE, seopts, 1);
114
115    if (!sehandle) {
116        fprintf(stderr, "Warning:  No file_contexts\n");
117        fprintf(cmd_pipe, "ui_print Warning: No file_contexts\n");
118    }
119#endif
120
121    // Evaluate the parsed script.
122
123    UpdaterInfo updater_info;
124    updater_info.cmd_pipe = cmd_pipe;
125    updater_info.package_zip = &za;
126    updater_info.version = atoi(version);
127
128    State state;
129    state.cookie = &updater_info;
130    state.script = script;
131    state.errmsg = NULL;
132
133    char* result = Evaluate(&state, root);
134    if (result == NULL) {
135        if (state.errmsg == NULL) {
136            fprintf(stderr, "script aborted (no error message)\n");
137            fprintf(cmd_pipe, "ui_print script aborted (no error message)\n");
138        } else {
139            fprintf(stderr, "script aborted: %s\n", state.errmsg);
140            char* line = strtok(state.errmsg, "\n");
141            while (line) {
142                fprintf(cmd_pipe, "ui_print %s\n", line);
143                line = strtok(NULL, "\n");
144            }
145            fprintf(cmd_pipe, "ui_print\n");
146        }
147        free(state.errmsg);
148        return 7;
149    } else {
150        fprintf(stderr, "script result was [%s]\n", result);
151        free(result);
152    }
153
154    if (updater_info.package_zip) {
155        mzCloseZipArchive(updater_info.package_zip);
156    }
157    free(script);
158
159    return 0;
160}
161