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-rw-r--r--applypatch/applypatch.c1359
1 files changed, 637 insertions, 722 deletions
diff --git a/applypatch/applypatch.c b/applypatch/applypatch.c
index daf372907..99d366165 100644
--- a/applypatch/applypatch.c
+++ b/applypatch/applypatch.c
@@ -28,6 +28,7 @@
#include "mincrypt/sha.h"
#include "applypatch.h"
#include "mtdutils/mtdutils.h"
+#include "edify/expr.h"
int SaveFileContents(const char* filename, FileContents file);
int LoadMTDContents(const char* filename, FileContents* file);
@@ -39,57 +40,57 @@ static int mtd_partitions_scanned = 0;
// Read a file into memory; store it and its associated metadata in
// *file. Return 0 on success.
int LoadFileContents(const char* filename, FileContents* file) {
- file->data = NULL;
+ file->data = NULL;
- // A special 'filename' beginning with "MTD:" means to load the
- // contents of an MTD partition.
- if (strncmp(filename, "MTD:", 4) == 0) {
- return LoadMTDContents(filename, file);
- }
+ // A special 'filename' beginning with "MTD:" means to load the
+ // contents of an MTD partition.
+ if (strncmp(filename, "MTD:", 4) == 0) {
+ return LoadMTDContents(filename, file);
+ }
- if (stat(filename, &file->st) != 0) {
- printf("failed to stat \"%s\": %s\n", filename, strerror(errno));
- return -1;
- }
+ if (stat(filename, &file->st) != 0) {
+ printf("failed to stat \"%s\": %s\n", filename, strerror(errno));
+ return -1;
+ }
- file->size = file->st.st_size;
- file->data = malloc(file->size);
+ file->size = file->st.st_size;
+ file->data = malloc(file->size);
- FILE* f = fopen(filename, "rb");
- if (f == NULL) {
- printf("failed to open \"%s\": %s\n", filename, strerror(errno));
- free(file->data);
- file->data = NULL;
- return -1;
- }
+ FILE* f = fopen(filename, "rb");
+ if (f == NULL) {
+ printf("failed to open \"%s\": %s\n", filename, strerror(errno));
+ free(file->data);
+ file->data = NULL;
+ return -1;
+ }
- size_t bytes_read = fread(file->data, 1, file->size, f);
- if (bytes_read != file->size) {
- printf("short read of \"%s\" (%d bytes of %d)\n",
- filename, bytes_read, file->size);
- free(file->data);
- file->data = NULL;
- return -1;
- }
- fclose(f);
+ ssize_t bytes_read = fread(file->data, 1, file->size, f);
+ if (bytes_read != file->size) {
+ printf("short read of \"%s\" (%ld bytes of %ld)\n",
+ filename, (long)bytes_read, (long)file->size);
+ free(file->data);
+ file->data = NULL;
+ return -1;
+ }
+ fclose(f);
- SHA(file->data, file->size, file->sha1);
- return 0;
+ SHA(file->data, file->size, file->sha1);
+ return 0;
}
static size_t* size_array;
// comparison function for qsort()ing an int array of indexes into
// size_array[].
static int compare_size_indices(const void* a, const void* b) {
- int aa = *(int*)a;
- int bb = *(int*)b;
- if (size_array[aa] < size_array[bb]) {
- return -1;
- } else if (size_array[aa] > size_array[bb]) {
- return 1;
- } else {
- return 0;
- }
+ int aa = *(int*)a;
+ int bb = *(int*)b;
+ if (size_array[aa] < size_array[bb]) {
+ return -1;
+ } else if (size_array[aa] > size_array[bb]) {
+ return 1;
+ } else {
+ return 0;
+ }
}
void FreeFileContents(FileContents* file) {
@@ -113,239 +114,240 @@ void FreeFileContents(FileContents* file) {
// hash of the data, and we'll do the load expecting to find one of
// those hashes.
int LoadMTDContents(const char* filename, FileContents* file) {
- char* copy = strdup(filename);
- const char* magic = strtok(copy, ":");
- if (strcmp(magic, "MTD") != 0) {
- printf("LoadMTDContents called with bad filename (%s)\n",
- filename);
- return -1;
- }
- const char* partition = strtok(NULL, ":");
-
- int i;
- int colons = 0;
- for (i = 0; filename[i] != '\0'; ++i) {
- if (filename[i] == ':') {
- ++colons;
- }
- }
- if (colons < 3 || colons%2 == 0) {
- printf("LoadMTDContents called with bad filename (%s)\n",
- filename);
- }
-
- int pairs = (colons-1)/2; // # of (size,sha1) pairs in filename
- int* index = malloc(pairs * sizeof(int));
- size_t* size = malloc(pairs * sizeof(size_t));
- char** sha1sum = malloc(pairs * sizeof(char*));
-
- for (i = 0; i < pairs; ++i) {
- const char* size_str = strtok(NULL, ":");
- size[i] = strtol(size_str, NULL, 10);
- if (size[i] == 0) {
- printf("LoadMTDContents called with bad size (%s)\n", filename);
- return -1;
- }
- sha1sum[i] = strtok(NULL, ":");
- index[i] = i;
- }
-
- // sort the index[] array so it indexes the pairs in order of
- // increasing size.
- size_array = size;
- qsort(index, pairs, sizeof(int), compare_size_indices);
-
- if (!mtd_partitions_scanned) {
- mtd_scan_partitions();
- mtd_partitions_scanned = 1;
- }
-
- const MtdPartition* mtd = mtd_find_partition_by_name(partition);
- if (mtd == NULL) {
- printf("mtd partition \"%s\" not found (loading %s)\n",
- partition, filename);
- return -1;
- }
-
- MtdReadContext* ctx = mtd_read_partition(mtd);
- if (ctx == NULL) {
- printf("failed to initialize read of mtd partition \"%s\"\n",
- partition);
- return -1;
- }
-
- SHA_CTX sha_ctx;
- SHA_init(&sha_ctx);
- uint8_t parsed_sha[SHA_DIGEST_SIZE];
-
- // allocate enough memory to hold the largest size.
- file->data = malloc(size[index[pairs-1]]);
- char* p = (char*)file->data;
- file->size = 0; // # bytes read so far
-
- for (i = 0; i < pairs; ++i) {
- // Read enough additional bytes to get us up to the next size
- // (again, we're trying the possibilities in order of increasing
- // size).
- size_t next = size[index[i]] - file->size;
- size_t read = 0;
- if (next > 0) {
- read = mtd_read_data(ctx, p, next);
- if (next != read) {
- printf("short read (%d bytes of %d) for partition \"%s\"\n",
- read, next, partition);
- free(file->data);
- file->data = NULL;
+ char* copy = strdup(filename);
+ const char* magic = strtok(copy, ":");
+ if (strcmp(magic, "MTD") != 0) {
+ printf("LoadMTDContents called with bad filename (%s)\n",
+ filename);
return -1;
- }
- SHA_update(&sha_ctx, p, read);
- file->size += read;
}
+ const char* partition = strtok(NULL, ":");
- // Duplicate the SHA context and finalize the duplicate so we can
- // check it against this pair's expected hash.
- SHA_CTX temp_ctx;
- memcpy(&temp_ctx, &sha_ctx, sizeof(SHA_CTX));
- const uint8_t* sha_so_far = SHA_final(&temp_ctx);
+ int i;
+ int colons = 0;
+ for (i = 0; filename[i] != '\0'; ++i) {
+ if (filename[i] == ':') {
+ ++colons;
+ }
+ }
+ if (colons < 3 || colons%2 == 0) {
+ printf("LoadMTDContents called with bad filename (%s)\n",
+ filename);
+ }
- if (ParseSha1(sha1sum[index[i]], parsed_sha) != 0) {
- printf("failed to parse sha1 %s in %s\n",
- sha1sum[index[i]], filename);
- free(file->data);
- file->data = NULL;
- return -1;
+ int pairs = (colons-1)/2; // # of (size,sha1) pairs in filename
+ int* index = malloc(pairs * sizeof(int));
+ size_t* size = malloc(pairs * sizeof(size_t));
+ char** sha1sum = malloc(pairs * sizeof(char*));
+
+ for (i = 0; i < pairs; ++i) {
+ const char* size_str = strtok(NULL, ":");
+ size[i] = strtol(size_str, NULL, 10);
+ if (size[i] == 0) {
+ printf("LoadMTDContents called with bad size (%s)\n", filename);
+ return -1;
+ }
+ sha1sum[i] = strtok(NULL, ":");
+ index[i] = i;
}
- if (memcmp(sha_so_far, parsed_sha, SHA_DIGEST_SIZE) == 0) {
- // we have a match. stop reading the partition; we'll return
- // the data we've read so far.
- printf("mtd read matched size %d sha %s\n",
- size[index[i]], sha1sum[index[i]]);
- break;
+ // sort the index[] array so it indexes the pairs in order of
+ // increasing size.
+ size_array = size;
+ qsort(index, pairs, sizeof(int), compare_size_indices);
+
+ if (!mtd_partitions_scanned) {
+ mtd_scan_partitions();
+ mtd_partitions_scanned = 1;
}
- p += read;
- }
+ const MtdPartition* mtd = mtd_find_partition_by_name(partition);
+ if (mtd == NULL) {
+ printf("mtd partition \"%s\" not found (loading %s)\n",
+ partition, filename);
+ return -1;
+ }
- mtd_read_close(ctx);
+ MtdReadContext* ctx = mtd_read_partition(mtd);
+ if (ctx == NULL) {
+ printf("failed to initialize read of mtd partition \"%s\"\n",
+ partition);
+ return -1;
+ }
- if (i == pairs) {
- // Ran off the end of the list of (size,sha1) pairs without
- // finding a match.
- printf("contents of MTD partition \"%s\" didn't match %s\n",
- partition, filename);
- free(file->data);
- file->data = NULL;
- return -1;
- }
+ SHA_CTX sha_ctx;
+ SHA_init(&sha_ctx);
+ uint8_t parsed_sha[SHA_DIGEST_SIZE];
+
+ // allocate enough memory to hold the largest size.
+ file->data = malloc(size[index[pairs-1]]);
+ char* p = (char*)file->data;
+ file->size = 0; // # bytes read so far
+
+ for (i = 0; i < pairs; ++i) {
+ // Read enough additional bytes to get us up to the next size
+ // (again, we're trying the possibilities in order of increasing
+ // size).
+ size_t next = size[index[i]] - file->size;
+ size_t read = 0;
+ if (next > 0) {
+ read = mtd_read_data(ctx, p, next);
+ if (next != read) {
+ printf("short read (%d bytes of %d) for partition \"%s\"\n",
+ read, next, partition);
+ free(file->data);
+ file->data = NULL;
+ return -1;
+ }
+ SHA_update(&sha_ctx, p, read);
+ file->size += read;
+ }
+
+ // Duplicate the SHA context and finalize the duplicate so we can
+ // check it against this pair's expected hash.
+ SHA_CTX temp_ctx;
+ memcpy(&temp_ctx, &sha_ctx, sizeof(SHA_CTX));
+ const uint8_t* sha_so_far = SHA_final(&temp_ctx);
+
+ if (ParseSha1(sha1sum[index[i]], parsed_sha) != 0) {
+ printf("failed to parse sha1 %s in %s\n",
+ sha1sum[index[i]], filename);
+ free(file->data);
+ file->data = NULL;
+ return -1;
+ }
+
+ if (memcmp(sha_so_far, parsed_sha, SHA_DIGEST_SIZE) == 0) {
+ // we have a match. stop reading the partition; we'll return
+ // the data we've read so far.
+ printf("mtd read matched size %d sha %s\n",
+ size[index[i]], sha1sum[index[i]]);
+ break;
+ }
- const uint8_t* sha_final = SHA_final(&sha_ctx);
- for (i = 0; i < SHA_DIGEST_SIZE; ++i) {
- file->sha1[i] = sha_final[i];
- }
+ p += read;
+ }
+
+ mtd_read_close(ctx);
+
+ if (i == pairs) {
+ // Ran off the end of the list of (size,sha1) pairs without
+ // finding a match.
+ printf("contents of MTD partition \"%s\" didn't match %s\n",
+ partition, filename);
+ free(file->data);
+ file->data = NULL;
+ return -1;
+ }
+
+ const uint8_t* sha_final = SHA_final(&sha_ctx);
+ for (i = 0; i < SHA_DIGEST_SIZE; ++i) {
+ file->sha1[i] = sha_final[i];
+ }
- // Fake some stat() info.
- file->st.st_mode = 0644;
- file->st.st_uid = 0;
- file->st.st_gid = 0;
+ // Fake some stat() info.
+ file->st.st_mode = 0644;
+ file->st.st_uid = 0;
+ file->st.st_gid = 0;
- free(copy);
- free(index);
- free(size);
- free(sha1sum);
+ free(copy);
+ free(index);
+ free(size);
+ free(sha1sum);
- return 0;
+ return 0;
}
// Save the contents of the given FileContents object under the given
// filename. Return 0 on success.
int SaveFileContents(const char* filename, FileContents file) {
- int fd = open(filename, O_WRONLY | O_CREAT | O_TRUNC);
- if (fd < 0) {
- printf("failed to open \"%s\" for write: %s\n",
- filename, strerror(errno));
- return -1;
- }
+ int fd = open(filename, O_WRONLY | O_CREAT | O_TRUNC);
+ if (fd < 0) {
+ printf("failed to open \"%s\" for write: %s\n",
+ filename, strerror(errno));
+ return -1;
+ }
- size_t bytes_written = FileSink(file.data, file.size, &fd);
- if (bytes_written != file.size) {
- printf("short write of \"%s\" (%d bytes of %d) (%s)\n",
- filename, bytes_written, file.size, strerror(errno));
+ ssize_t bytes_written = FileSink(file.data, file.size, &fd);
+ if (bytes_written != file.size) {
+ printf("short write of \"%s\" (%ld bytes of %ld) (%s)\n",
+ filename, (long)bytes_written, (long)file.size,
+ strerror(errno));
+ close(fd);
+ return -1;
+ }
+ fsync(fd);
close(fd);
- return -1;
- }
- fsync(fd);
- close(fd);
- if (chmod(filename, file.st.st_mode) != 0) {
- printf("chmod of \"%s\" failed: %s\n", filename, strerror(errno));
- return -1;
- }
- if (chown(filename, file.st.st_uid, file.st.st_gid) != 0) {
- printf("chown of \"%s\" failed: %s\n", filename, strerror(errno));
- return -1;
- }
+ if (chmod(filename, file.st.st_mode) != 0) {
+ printf("chmod of \"%s\" failed: %s\n", filename, strerror(errno));
+ return -1;
+ }
+ if (chown(filename, file.st.st_uid, file.st.st_gid) != 0) {
+ printf("chown of \"%s\" failed: %s\n", filename, strerror(errno));
+ return -1;
+ }
- return 0;
+ return 0;
}
// Write a memory buffer to target_mtd partition, a string of the form
// "MTD:<partition>[:...]". Return 0 on success.
int WriteToMTDPartition(unsigned char* data, size_t len,
const char* target_mtd) {
- char* partition = strchr(target_mtd, ':');
- if (partition == NULL) {
- printf("bad MTD target name \"%s\"\n", target_mtd);
- return -1;
- }
- ++partition;
- // Trim off anything after a colon, eg "MTD:boot:blah:blah:blah...".
- // We want just the partition name "boot".
- partition = strdup(partition);
- char* end = strchr(partition, ':');
- if (end != NULL)
- *end = '\0';
-
- if (!mtd_partitions_scanned) {
- mtd_scan_partitions();
- mtd_partitions_scanned = 1;
- }
-
- const MtdPartition* mtd = mtd_find_partition_by_name(partition);
- if (mtd == NULL) {
- printf("mtd partition \"%s\" not found for writing\n", partition);
- return -1;
- }
+ char* partition = strchr(target_mtd, ':');
+ if (partition == NULL) {
+ printf("bad MTD target name \"%s\"\n", target_mtd);
+ return -1;
+ }
+ ++partition;
+ // Trim off anything after a colon, eg "MTD:boot:blah:blah:blah...".
+ // We want just the partition name "boot".
+ partition = strdup(partition);
+ char* end = strchr(partition, ':');
+ if (end != NULL)
+ *end = '\0';
+
+ if (!mtd_partitions_scanned) {
+ mtd_scan_partitions();
+ mtd_partitions_scanned = 1;
+ }
- MtdWriteContext* ctx = mtd_write_partition(mtd);
- if (ctx == NULL) {
- printf("failed to init mtd partition \"%s\" for writing\n",
- partition);
- return -1;
- }
+ const MtdPartition* mtd = mtd_find_partition_by_name(partition);
+ if (mtd == NULL) {
+ printf("mtd partition \"%s\" not found for writing\n", partition);
+ return -1;
+ }
- size_t written = mtd_write_data(ctx, (char*)data, len);
- if (written != len) {
- printf("only wrote %d of %d bytes to MTD %s\n",
- written, len, partition);
- mtd_write_close(ctx);
- return -1;
- }
+ MtdWriteContext* ctx = mtd_write_partition(mtd);
+ if (ctx == NULL) {
+ printf("failed to init mtd partition \"%s\" for writing\n",
+ partition);
+ return -1;
+ }
- if (mtd_erase_blocks(ctx, -1) < 0) {
- printf("error finishing mtd write of %s\n", partition);
- mtd_write_close(ctx);
- return -1;
- }
+ size_t written = mtd_write_data(ctx, (char*)data, len);
+ if (written != len) {
+ printf("only wrote %d of %d bytes to MTD %s\n",
+ written, len, partition);
+ mtd_write_close(ctx);
+ return -1;
+ }
- if (mtd_write_close(ctx)) {
- printf("error closing mtd write of %s\n", partition);
- return -1;
- }
+ if (mtd_erase_blocks(ctx, -1) < 0) {
+ printf("error finishing mtd write of %s\n", partition);
+ mtd_write_close(ctx);
+ return -1;
+ }
- free(partition);
- return 0;
+ if (mtd_write_close(ctx)) {
+ printf("error closing mtd write of %s\n", partition);
+ return -1;
+ }
+
+ free(partition);
+ return 0;
}
@@ -354,547 +356,460 @@ int WriteToMTDPartition(unsigned char* data, size_t len,
// the form "<digest>:<anything>". Return 0 on success, -1 on any
// error.
int ParseSha1(const char* str, uint8_t* digest) {
- int i;
- const char* ps = str;
- uint8_t* pd = digest;
- for (i = 0; i < SHA_DIGEST_SIZE * 2; ++i, ++ps) {
- int digit;
- if (*ps >= '0' && *ps <= '9') {
- digit = *ps - '0';
- } else if (*ps >= 'a' && *ps <= 'f') {
- digit = *ps - 'a' + 10;
- } else if (*ps >= 'A' && *ps <= 'F') {
- digit = *ps - 'A' + 10;
- } else {
- return -1;
- }
- if (i % 2 == 0) {
- *pd = digit << 4;
- } else {
- *pd |= digit;
- ++pd;
- }
- }
- if (*ps != '\0' && *ps != ':') return -1;
- return 0;
-}
-
-// Parse arguments (which should be of the form "<sha1>" or
-// "<sha1>:<filename>" into the array *patches, returning the number
-// of Patch objects in *num_patches. Return 0 on success.
-int ParseShaArgs(int argc, char** argv, Patch** patches, int* num_patches) {
- *num_patches = argc;
- *patches = malloc(*num_patches * sizeof(Patch));
-
- int i;
- for (i = 0; i < *num_patches; ++i) {
- if (ParseSha1(argv[i], (*patches)[i].sha1) != 0) {
- printf("failed to parse sha1 \"%s\"\n", argv[i]);
- return -1;
- }
- if (argv[i][SHA_DIGEST_SIZE*2] == '\0') {
- (*patches)[i].patch_filename = NULL;
- } else if (argv[i][SHA_DIGEST_SIZE*2] == ':') {
- (*patches)[i].patch_filename = argv[i] + (SHA_DIGEST_SIZE*2+1);
- } else {
- printf("failed to parse filename \"%s\"\n", argv[i]);
- return -1;
+ int i;
+ const char* ps = str;
+ uint8_t* pd = digest;
+ for (i = 0; i < SHA_DIGEST_SIZE * 2; ++i, ++ps) {
+ int digit;
+ if (*ps >= '0' && *ps <= '9') {
+ digit = *ps - '0';
+ } else if (*ps >= 'a' && *ps <= 'f') {
+ digit = *ps - 'a' + 10;
+ } else if (*ps >= 'A' && *ps <= 'F') {
+ digit = *ps - 'A' + 10;
+ } else {
+ return -1;
+ }
+ if (i % 2 == 0) {
+ *pd = digit << 4;
+ } else {
+ *pd |= digit;
+ ++pd;
+ }
}
- }
-
- return 0;
+ if (*ps != '\0') return -1;
+ return 0;
}
-// Search an array of Patch objects for one matching the given sha1.
-// Return the Patch object on success, or NULL if no match is found.
-const Patch* FindMatchingPatch(uint8_t* sha1, Patch* patches, int num_patches) {
- int i;
- for (i = 0; i < num_patches; ++i) {
- if (memcmp(patches[i].sha1, sha1, SHA_DIGEST_SIZE) == 0) {
- return patches+i;
+// Search an array of sha1 strings for one matching the given sha1.
+// Return the index of the match on success, or -1 if no match is
+// found.
+int FindMatchingPatch(uint8_t* sha1, char** const patch_sha1_str,
+ int num_patches) {
+ int i;
+ uint8_t patch_sha1[SHA_DIGEST_SIZE];
+ for (i = 0; i < num_patches; ++i) {
+ if (ParseSha1(patch_sha1_str[i], patch_sha1) == 0 &&
+ memcmp(patch_sha1, sha1, SHA_DIGEST_SIZE) == 0) {
+ return i;
+ }
}
- }
- return NULL;
+ return -1;
}
// Returns 0 if the contents of the file (argv[2]) or the cached file
// match any of the sha1's on the command line (argv[3:]). Returns
// nonzero otherwise.
-int CheckMode(int argc, char** argv) {
- if (argc < 3) {
- printf("no filename given\n");
- return 2;
- }
-
- int num_patches;
- Patch* patches;
- if (ParseShaArgs(argc-3, argv+3, &patches, &num_patches) != 0) { return 1; }
-
- FileContents file;
- file.data = NULL;
-
- // It's okay to specify no sha1s; the check will pass if the
- // LoadFileContents is successful. (Useful for reading MTD
- // partitions, where the filename encodes the sha1s; no need to
- // check them twice.)
- if (LoadFileContents(argv[2], &file) != 0 ||
- (num_patches > 0 &&
- FindMatchingPatch(file.sha1, patches, num_patches) == NULL)) {
- printf("file \"%s\" doesn't have any of expected "
- "sha1 sums; checking cache\n", argv[2]);
-
- free(file.data);
-
- // If the source file is missing or corrupted, it might be because
- // we were killed in the middle of patching it. A copy of it
- // should have been made in CACHE_TEMP_SOURCE. If that file
- // exists and matches the sha1 we're looking for, the check still
- // passes.
-
- if (LoadFileContents(CACHE_TEMP_SOURCE, &file) != 0) {
- printf("failed to load cache file\n");
- return 1;
- }
+int applypatch_check(const char* filename,
+ int num_patches, char** const patch_sha1_str) {
+ FileContents file;
+ file.data = NULL;
+
+ // It's okay to specify no sha1s; the check will pass if the
+ // LoadFileContents is successful. (Useful for reading MTD
+ // partitions, where the filename encodes the sha1s; no need to
+ // check them twice.)
+ if (LoadFileContents(filename, &file) != 0 ||
+ (num_patches > 0 &&
+ FindMatchingPatch(file.sha1, patch_sha1_str, num_patches) < 0)) {
+ printf("file \"%s\" doesn't have any of expected "
+ "sha1 sums; checking cache\n", filename);
+
+ free(file.data);
+
+ // If the source file is missing or corrupted, it might be because
+ // we were killed in the middle of patching it. A copy of it
+ // should have been made in CACHE_TEMP_SOURCE. If that file
+ // exists and matches the sha1 we're looking for, the check still
+ // passes.
+
+ if (LoadFileContents(CACHE_TEMP_SOURCE, &file) != 0) {
+ printf("failed to load cache file\n");
+ return 1;
+ }
- if (FindMatchingPatch(file.sha1, patches, num_patches) == NULL) {
- printf("cache bits don't match any sha1 for \"%s\"\n",
- argv[2]);
- return 1;
+ if (FindMatchingPatch(file.sha1, patch_sha1_str, num_patches) < 0) {
+ printf("cache bits don't match any sha1 for \"%s\"\n", filename);
+ free(file.data);
+ return 1;
+ }
}
- }
- free(file.data);
- return 0;
+ free(file.data);
+ return 0;
}
int ShowLicenses() {
- ShowBSDiffLicense();
- return 0;
+ ShowBSDiffLicense();
+ return 0;
}
ssize_t FileSink(unsigned char* data, ssize_t len, void* token) {
- int fd = *(int *)token;
- ssize_t done = 0;
- ssize_t wrote;
- while (done < (ssize_t) len) {
- wrote = write(fd, data+done, len-done);
- if (wrote <= 0) {
- printf("error writing %d bytes: %s\n", (int)(len-done), strerror(errno));
- return done;
- }
- done += wrote;
- }
- printf("wrote %d bytes to output\n", (int)done);
- return done;
+ int fd = *(int *)token;
+ ssize_t done = 0;
+ ssize_t wrote;
+ while (done < (ssize_t) len) {
+ wrote = write(fd, data+done, len-done);
+ if (wrote <= 0) {
+ printf("error writing %d bytes: %s\n", (int)(len-done), strerror(errno));
+ return done;
+ }
+ done += wrote;
+ }
+ return done;
}
typedef struct {
- unsigned char* buffer;
- ssize_t size;
- ssize_t pos;
+ unsigned char* buffer;
+ ssize_t size;
+ ssize_t pos;
} MemorySinkInfo;
ssize_t MemorySink(unsigned char* data, ssize_t len, void* token) {
- MemorySinkInfo* msi = (MemorySinkInfo*)token;
- if (msi->size - msi->pos < len) {
- return -1;
- }
- memcpy(msi->buffer + msi->pos, data, len);
- msi->pos += len;
- return len;
+ MemorySinkInfo* msi = (MemorySinkInfo*)token;
+ if (msi->size - msi->pos < len) {
+ return -1;
+ }
+ memcpy(msi->buffer + msi->pos, data, len);
+ msi->pos += len;
+ return len;
}
// Return the amount of free space (in bytes) on the filesystem
// containing filename. filename must exist. Return -1 on error.
size_t FreeSpaceForFile(const char* filename) {
- struct statfs sf;
- if (statfs(filename, &sf) != 0) {
- printf("failed to statfs %s: %s\n", filename, strerror(errno));
- return -1;
- }
- return sf.f_bsize * sf.f_bfree;
+ struct statfs sf;
+ if (statfs(filename, &sf) != 0) {
+ printf("failed to statfs %s: %s\n", filename, strerror(errno));
+ return -1;
+ }
+ return sf.f_bsize * sf.f_bfree;
+}
+
+int CacheSizeCheck(size_t bytes) {
+ if (MakeFreeSpaceOnCache(bytes) < 0) {
+ printf("unable to make %ld bytes available on /cache\n", (long)bytes);
+ return 1;
+ } else {
+ return 0;
+ }
}
-// This program applies binary patches to files in a way that is safe
+
+// This function applies binary patches to files in a way that is safe
// (the original file is not touched until we have the desired
// replacement for it) and idempotent (it's okay to run this program
// multiple times).
//
-// - if the sha1 hash of <tgt-file> is <tgt-sha1>, does nothing and exits
-// successfully.
+// - if the sha1 hash of <target_filename> is <target_sha1_string>,
+// does nothing and exits successfully.
//
-// - otherwise, if the sha1 hash of <src-file> is <src-sha1>, applies the
-// bsdiff <patch> to <src-file> to produce a new file (the type of patch
-// is automatically detected from the file header). If that new
-// file has sha1 hash <tgt-sha1>, moves it to replace <tgt-file>, and
-// exits successfully. Note that if <src-file> and <tgt-file> are
-// not the same, <src-file> is NOT deleted on success. <tgt-file>
-// may be the string "-" to mean "the same as src-file".
+// - otherwise, if the sha1 hash of <source_filename> is one of the
+// entries in <patch_sha1_str>, the corresponding patch from
+// <patch_data> (which must be a VAL_BLOB) is applied to produce a
+// new file (the type of patch is automatically detected from the
+// blob daat). If that new file has sha1 hash <target_sha1_str>,
+// moves it to replace <target_filename>, and exits successfully.
+// Note that if <source_filename> and <target_filename> are not the
+// same, <source_filename> is NOT deleted on success.
+// <target_filename> may be the string "-" to mean "the same as
+// source_filename".
//
// - otherwise, or if any error is encountered, exits with non-zero
// status.
//
-// <src-file> (or <file> in check mode) may refer to an MTD partition
-// to read the source data. See the comments for the
-// LoadMTDContents() function above for the format of such a filename.
-//
-//
-// As you might guess from the arguments, this function used to be
-// main(); it was split out this way so applypatch could be built as a
-// static library and linked into other executables as well. In the
-// future only the library form will exist; we will not need to build
-// this as a standalone executable.
-//
-// The arguments to this function are just the command-line of the
-// standalone executable:
-//
-// <src-file> <tgt-file> <tgt-sha1> <tgt-size> [<src-sha1>:<patch> ...]
-// to apply a patch. Returns 0 on success, 1 on failure.
-//
-// "-c" <file> [<sha1> ...]
-// to check a file's contents against zero or more sha1s. Returns
-// 0 if it matches any of them, 1 if it doesn't.
-//
-// "-s" <bytes>
-// returns 0 if enough free space is available on /cache; 1 if it
-// does not.
-//
-// "-l"
-// shows open-source license information and returns 0.
-//
-// This function returns 2 if the arguments are not understood (in the
-// standalone executable, this causes the usage message to be
-// printed).
-//
-// TODO: make the interface more sensible for use as a library.
-
-int applypatch(int argc, char** argv) {
- if (argc < 2) {
- return 2;
- }
+// <source_filename> may refer to an MTD partition to read the source
+// data. See the comments for the LoadMTDContents() function above
+// for the format of such a filename.
+
+int applypatch(const char* source_filename,
+ const char* target_filename,
+ const char* target_sha1_str,
+ size_t target_size,
+ int num_patches,
+ char** const patch_sha1_str,
+ Value** patch_data) {
+ printf("\napplying patch to %s\n", source_filename);
+
+ if (target_filename[0] == '-' &&
+ target_filename[1] == '\0') {
+ target_filename = source_filename;
+ }
- if (strncmp(argv[1], "-l", 3) == 0) {
- return ShowLicenses();
- }
+ uint8_t target_sha1[SHA_DIGEST_SIZE];
+ if (ParseSha1(target_sha1_str, target_sha1) != 0) {
+ printf("failed to parse tgt-sha1 \"%s\"\n", target_sha1_str);
+ return 1;
+ }
- if (strncmp(argv[1], "-c", 3) == 0) {
- return CheckMode(argc, argv);
- }
+ FileContents copy_file;
+ FileContents source_file;
+ const Value* source_patch_value = NULL;
+ const Value* copy_patch_value = NULL;
+ int made_copy = 0;
+
+ // We try to load the target file into the source_file object.
+ if (LoadFileContents(target_filename, &source_file) == 0) {
+ if (memcmp(source_file.sha1, target_sha1, SHA_DIGEST_SIZE) == 0) {
+ // The early-exit case: the patch was already applied, this file
+ // has the desired hash, nothing for us to do.
+ printf("\"%s\" is already target; no patch needed\n",
+ target_filename);
+ return 0;
+ }
+ }
- if (strncmp(argv[1], "-s", 3) == 0) {
- if (argc != 3) {
- return 2;
+ if (source_file.data == NULL ||
+ (target_filename != source_filename &&
+ strcmp(target_filename, source_filename) != 0)) {
+ // Need to load the source file: either we failed to load the
+ // target file, or we did but it's different from the source file.
+ free(source_file.data);
+ LoadFileContents(source_filename, &source_file);
}
- size_t bytes = strtol(argv[2], NULL, 10);
- if (MakeFreeSpaceOnCache(bytes) < 0) {
- printf("unable to make %ld bytes available on /cache\n", (long)bytes);
- return 1;
- } else {
- return 0;
- }
- }
-
- uint8_t target_sha1[SHA_DIGEST_SIZE];
-
- const char* source_filename = argv[1];
- const char* target_filename = argv[2];
- if (target_filename[0] == '-' &&
- target_filename[1] == '\0') {
- target_filename = source_filename;
- }
-
- printf("\napplying patch to %s\n", source_filename);
-
- if (ParseSha1(argv[3], target_sha1) != 0) {
- printf("failed to parse tgt-sha1 \"%s\"\n", argv[3]);
- return 1;
- }
-
- unsigned long target_size = strtoul(argv[4], NULL, 0);
-
- int num_patches;
- Patch* patches;
- if (ParseShaArgs(argc-5, argv+5, &patches, &num_patches) < 0) { return 1; }
-
- FileContents copy_file;
- FileContents source_file;
- const char* source_patch_filename = NULL;
- const char* copy_patch_filename = NULL;
- int made_copy = 0;
-
- // We try to load the target file into the source_file object.
- if (LoadFileContents(target_filename, &source_file) == 0) {
- if (memcmp(source_file.sha1, target_sha1, SHA_DIGEST_SIZE) == 0) {
- // The early-exit case: the patch was already applied, this file
- // has the desired hash, nothing for us to do.
- printf("\"%s\" is already target; no patch needed\n",
- target_filename);
- return 0;
- }
- }
-
- if (source_file.data == NULL ||
- (target_filename != source_filename &&
- strcmp(target_filename, source_filename) != 0)) {
- // Need to load the source file: either we failed to load the
- // target file, or we did but it's different from the source file.
- free(source_file.data);
- LoadFileContents(source_filename, &source_file);
- }
-
- if (source_file.data != NULL) {
- const Patch* to_use =
- FindMatchingPatch(source_file.sha1, patches, num_patches);
- if (to_use != NULL) {
- source_patch_filename = to_use->patch_filename;
- }
- }
-
- if (source_patch_filename == NULL) {
- free(source_file.data);
- printf("source file is bad; trying copy\n");
-
- if (LoadFileContents(CACHE_TEMP_SOURCE, &copy_file) < 0) {
- // fail.
- printf("failed to read copy file\n");
- return 1;
- }
-
- const Patch* to_use =
- FindMatchingPatch(copy_file.sha1, patches, num_patches);
- if (to_use != NULL) {
- copy_patch_filename = to_use->patch_filename;
- }
-
- if (copy_patch_filename == NULL) {
- // fail.
- printf("copy file doesn't match source SHA-1s either\n");
- return 1;
- }
- }
-
- int retry = 1;
- SHA_CTX ctx;
- int output;
- MemorySinkInfo msi;
- FileContents* source_to_use;
- char* outname;
-
- // assume that target_filename (eg "/system/app/Foo.apk") is located
- // on the same filesystem as its top-level directory ("/system").
- // We need something that exists for calling statfs().
- char target_fs[strlen(target_filename)+1];
- char* slash = strchr(target_filename+1, '/');
- if (slash != NULL) {
- int count = slash - target_filename;
- strncpy(target_fs, target_filename, count);
- target_fs[count] = '\0';
- } else {
- strcpy(target_fs, target_filename);
- }
-
- do {
- // Is there enough room in the target filesystem to hold the patched
- // file?
-
- if (strncmp(target_filename, "MTD:", 4) == 0) {
- // If the target is an MTD partition, we're actually going to
- // write the output to /tmp and then copy it to the partition.
- // statfs() always returns 0 blocks free for /tmp, so instead
- // we'll just assume that /tmp has enough space to hold the file.
-
- // We still write the original source to cache, in case the MTD
- // write is interrupted.
- if (MakeFreeSpaceOnCache(source_file.size) < 0) {
- printf("not enough free space on /cache\n");
- return 1;
- }
- if (SaveFileContents(CACHE_TEMP_SOURCE, source_file) < 0) {
- printf("failed to back up source file\n");
- return 1;
- }
- made_copy = 1;
- retry = 0;
- } else {
- int enough_space = 0;
- if (retry > 0) {
- size_t free_space = FreeSpaceForFile(target_fs);
- int enough_space =
- (free_space > (target_size * 3 / 2)); // 50% margin of error
- printf("target %ld bytes; free space %ld bytes; retry %d; enough %d\n",
- (long)target_size, (long)free_space, retry, enough_space);
- }
-
- if (!enough_space) {
- retry = 0;
- }
-
- if (!enough_space && source_patch_filename != NULL) {
- // Using the original source, but not enough free space. First
- // copy the source file to cache, then delete it from the original
- // location.
-
- if (strncmp(source_filename, "MTD:", 4) == 0) {
- // It's impossible to free space on the target filesystem by
- // deleting the source if the source is an MTD partition. If
- // we're ever in a state where we need to do this, fail.
- printf("not enough free space for target but source is MTD\n");
- return 1;
+
+ if (source_file.data != NULL) {
+ int to_use = FindMatchingPatch(source_file.sha1,
+ patch_sha1_str, num_patches);
+ if (to_use >= 0) {
+ source_patch_value = patch_data[to_use];
}
+ }
- if (MakeFreeSpaceOnCache(source_file.size) < 0) {
- printf("not enough free space on /cache\n");
- return 1;
+ if (source_patch_value == NULL) {
+ free(source_file.data);
+ printf("source file is bad; trying copy\n");
+
+ if (LoadFileContents(CACHE_TEMP_SOURCE, &copy_file) < 0) {
+ // fail.
+ printf("failed to read copy file\n");
+ return 1;
}
- if (SaveFileContents(CACHE_TEMP_SOURCE, source_file) < 0) {
- printf("failed to back up source file\n");
- return 1;
+ int to_use = FindMatchingPatch(copy_file.sha1,
+ patch_sha1_str, num_patches);
+ if (to_use > 0) {
+ copy_patch_value = patch_data[to_use];
}
- made_copy = 1;
- unlink(source_filename);
- size_t free_space = FreeSpaceForFile(target_fs);
- printf("(now %ld bytes free for target)\n", (long)free_space);
- }
+ if (copy_patch_value == NULL) {
+ // fail.
+ printf("copy file doesn't match source SHA-1s either\n");
+ return 1;
+ }
}
- const char* patch_filename;
- if (source_patch_filename != NULL) {
- source_to_use = &source_file;
- patch_filename = source_patch_filename;
- } else {
- source_to_use = &copy_file;
- patch_filename = copy_patch_filename;
- }
-
- SinkFn sink = NULL;
- void* token = NULL;
- output = -1;
- outname = NULL;
- if (strncmp(target_filename, "MTD:", 4) == 0) {
- // We store the decoded output in memory.
- msi.buffer = malloc(target_size);
- if (msi.buffer == NULL) {
- printf("failed to alloc %ld bytes for output\n",
- (long)target_size);
- return 1;
- }
- msi.pos = 0;
- msi.size = target_size;
- sink = MemorySink;
- token = &msi;
- } else {
- // We write the decoded output to "<tgt-file>.patch".
- outname = (char*)malloc(strlen(target_filename) + 10);
- strcpy(outname, target_filename);
- strcat(outname, ".patch");
-
- output = open(outname, O_WRONLY | O_CREAT | O_TRUNC);
- if (output < 0) {
- printf("failed to open output file %s: %s\n",
- outname, strerror(errno));
- return 1;
- }
- sink = FileSink;
- token = &output;
- }
-
-#define MAX_HEADER_LENGTH 8
- unsigned char header[MAX_HEADER_LENGTH];
- FILE* patchf = fopen(patch_filename, "rb");
- if (patchf == NULL) {
- printf("failed to open patch file %s: %s\n",
- patch_filename, strerror(errno));
- return 1;
- }
- int header_bytes_read = fread(header, 1, MAX_HEADER_LENGTH, patchf);
- fclose(patchf);
-
- SHA_init(&ctx);
-
- int result;
-
- if (header_bytes_read >= 4 &&
- header[0] == 0xd6 && header[1] == 0xc3 &&
- header[2] == 0xc4 && header[3] == 0) {
- // xdelta3 patches begin "VCD" (with the high bits set) followed
- // by a zero byte (the version number).
- printf("error: xdelta3 patches no longer supported\n");
- return 1;
- } else if (header_bytes_read >= 8 &&
- memcmp(header, "BSDIFF40", 8) == 0) {
- result = ApplyBSDiffPatch(source_to_use->data, source_to_use->size,
- patch_filename, 0, sink, token, &ctx);
- } else if (header_bytes_read >= 8 &&
- memcmp(header, "IMGDIFF", 7) == 0 &&
- (header[7] == '1' || header[7] == '2')) {
- result = ApplyImagePatch(source_to_use->data, source_to_use->size,
- patch_filename, sink, token, &ctx);
+ int retry = 1;
+ SHA_CTX ctx;
+ int output;
+ MemorySinkInfo msi;
+ FileContents* source_to_use;
+ char* outname;
+
+ // assume that target_filename (eg "/system/app/Foo.apk") is located
+ // on the same filesystem as its top-level directory ("/system").
+ // We need something that exists for calling statfs().
+ char target_fs[strlen(target_filename)+1];
+ char* slash = strchr(target_filename+1, '/');
+ if (slash != NULL) {
+ int count = slash - target_filename;
+ strncpy(target_fs, target_filename, count);
+ target_fs[count] = '\0';
} else {
- printf("Unknown patch file format\n");
- return 1;
+ strcpy(target_fs, target_filename);
}
- if (output >= 0) {
- fsync(output);
- close(output);
+ do {
+ // Is there enough room in the target filesystem to hold the patched
+ // file?
+
+ if (strncmp(target_filename, "MTD:", 4) == 0) {
+ // If the target is an MTD partition, we're actually going to
+ // write the output to /tmp and then copy it to the partition.
+ // statfs() always returns 0 blocks free for /tmp, so instead
+ // we'll just assume that /tmp has enough space to hold the file.
+
+ // We still write the original source to cache, in case the MTD
+ // write is interrupted.
+ if (MakeFreeSpaceOnCache(source_file.size) < 0) {
+ printf("not enough free space on /cache\n");
+ return 1;
+ }
+ if (SaveFileContents(CACHE_TEMP_SOURCE, source_file) < 0) {
+ printf("failed to back up source file\n");
+ return 1;
+ }
+ made_copy = 1;
+ retry = 0;
+ } else {
+ int enough_space = 0;
+ if (retry > 0) {
+ size_t free_space = FreeSpaceForFile(target_fs);
+ int enough_space =
+ (free_space > (target_size * 3 / 2)); // 50% margin of error
+ printf("target %ld bytes; free space %ld bytes; retry %d; enough %d\n",
+ (long)target_size, (long)free_space, retry, enough_space);
+ }
+
+ if (!enough_space) {
+ retry = 0;
+ }
+
+ if (!enough_space && source_patch_value != NULL) {
+ // Using the original source, but not enough free space. First
+ // copy the source file to cache, then delete it from the original
+ // location.
+
+ if (strncmp(source_filename, "MTD:", 4) == 0) {
+ // It's impossible to free space on the target filesystem by
+ // deleting the source if the source is an MTD partition. If
+ // we're ever in a state where we need to do this, fail.
+ printf("not enough free space for target but source is MTD\n");
+ return 1;
+ }
+
+ if (MakeFreeSpaceOnCache(source_file.size) < 0) {
+ printf("not enough free space on /cache\n");
+ return 1;
+ }
+
+ if (SaveFileContents(CACHE_TEMP_SOURCE, source_file) < 0) {
+ printf("failed to back up source file\n");
+ return 1;
+ }
+ made_copy = 1;
+ unlink(source_filename);
+
+ size_t free_space = FreeSpaceForFile(target_fs);
+ printf("(now %ld bytes free for target)\n", (long)free_space);
+ }
+ }
+
+ const Value* patch;
+ if (source_patch_value != NULL) {
+ source_to_use = &source_file;
+ patch = source_patch_value;
+ } else {
+ source_to_use = &copy_file;
+ patch = copy_patch_value;
+ }
+
+ if (patch->type != VAL_BLOB) {
+ printf("patch is not a blob\n");
+ return 1;
+ }
+
+ SinkFn sink = NULL;
+ void* token = NULL;
+ output = -1;
+ outname = NULL;
+ if (strncmp(target_filename, "MTD:", 4) == 0) {
+ // We store the decoded output in memory.
+ msi.buffer = malloc(target_size);
+ if (msi.buffer == NULL) {
+ printf("failed to alloc %ld bytes for output\n",
+ (long)target_size);
+ return 1;
+ }
+ msi.pos = 0;
+ msi.size = target_size;
+ sink = MemorySink;
+ token = &msi;
+ } else {
+ // We write the decoded output to "<tgt-file>.patch".
+ outname = (char*)malloc(strlen(target_filename) + 10);
+ strcpy(outname, target_filename);
+ strcat(outname, ".patch");
+
+ output = open(outname, O_WRONLY | O_CREAT | O_TRUNC);
+ if (output < 0) {
+ printf("failed to open output file %s: %s\n",
+ outname, strerror(errno));
+ return 1;
+ }
+ sink = FileSink;
+ token = &output;
+ }
+
+ char* header = patch->data;
+ ssize_t header_bytes_read = patch->size;
+
+ SHA_init(&ctx);
+
+ int result;
+
+ if (header_bytes_read >= 8 &&
+ memcmp(header, "BSDIFF40", 8) == 0) {
+ result = ApplyBSDiffPatch(source_to_use->data, source_to_use->size,
+ patch, 0, sink, token, &ctx);
+ } else if (header_bytes_read >= 8 &&
+ memcmp(header, "IMGDIFF2", 8) == 0) {
+ result = ApplyImagePatch(source_to_use->data, source_to_use->size,
+ patch, sink, token, &ctx);
+ } else {
+ printf("Unknown patch file format\n");
+ return 1;
+ }
+
+ if (output >= 0) {
+ fsync(output);
+ close(output);
+ }
+
+ if (result != 0) {
+ if (retry == 0) {
+ printf("applying patch failed\n");
+ return result != 0;
+ } else {
+ printf("applying patch failed; retrying\n");
+ }
+ if (outname != NULL) {
+ unlink(outname);
+ }
+ } else {
+ // succeeded; no need to retry
+ break;
+ }
+ } while (retry-- > 0);
+
+ const uint8_t* current_target_sha1 = SHA_final(&ctx);
+ if (memcmp(current_target_sha1, target_sha1, SHA_DIGEST_SIZE) != 0) {
+ printf("patch did not produce expected sha1\n");
+ return 1;
}
- if (result != 0) {
- if (retry == 0) {
- printf("applying patch failed\n");
- return result != 0;
- } else {
- printf("applying patch failed; retrying\n");
- }
- if (outname != NULL) {
- unlink(outname);
- }
+ if (output < 0) {
+ // Copy the temp file to the MTD partition.
+ if (WriteToMTDPartition(msi.buffer, msi.pos, target_filename) != 0) {
+ printf("write of patched data to %s failed\n", target_filename);
+ return 1;
+ }
+ free(msi.buffer);
} else {
- // succeeded; no need to retry
- break;
- }
- } while (retry-- > 0);
-
- const uint8_t* current_target_sha1 = SHA_final(&ctx);
- if (memcmp(current_target_sha1, target_sha1, SHA_DIGEST_SIZE) != 0) {
- printf("patch did not produce expected sha1\n");
- return 1;
- }
-
- if (output < 0) {
- // Copy the temp file to the MTD partition.
- if (WriteToMTDPartition(msi.buffer, msi.pos, target_filename) != 0) {
- printf("write of patched data to %s failed\n", target_filename);
- return 1;
- }
- free(msi.buffer);
- } else {
- // Give the .patch file the same owner, group, and mode of the
- // original source file.
- if (chmod(outname, source_to_use->st.st_mode) != 0) {
- printf("chmod of \"%s\" failed: %s\n", outname, strerror(errno));
- return 1;
- }
- if (chown(outname, source_to_use->st.st_uid,
- source_to_use->st.st_gid) != 0) {
- printf("chown of \"%s\" failed: %s\n", outname, strerror(errno));
- return 1;
- }
-
- // Finally, rename the .patch file to replace the target file.
- if (rename(outname, target_filename) != 0) {
- printf("rename of .patch to \"%s\" failed: %s\n",
- target_filename, strerror(errno));
- return 1;
- }
- }
-
- // If this run of applypatch created the copy, and we're here, we
- // can delete it.
- if (made_copy) unlink(CACHE_TEMP_SOURCE);
-
- // Success!
- return 0;
+ // Give the .patch file the same owner, group, and mode of the
+ // original source file.
+ if (chmod(outname, source_to_use->st.st_mode) != 0) {
+ printf("chmod of \"%s\" failed: %s\n", outname, strerror(errno));
+ return 1;
+ }
+ if (chown(outname, source_to_use->st.st_uid,
+ source_to_use->st.st_gid) != 0) {
+ printf("chown of \"%s\" failed: %s\n", outname, strerror(errno));
+ return 1;
+ }
+
+ // Finally, rename the .patch file to replace the target file.
+ if (rename(outname, target_filename) != 0) {
+ printf("rename of .patch to \"%s\" failed: %s\n",
+ target_filename, strerror(errno));
+ return 1;
+ }
+ }
+
+ // If this run of applypatch created the copy, and we're here, we
+ // can delete it.
+ if (made_copy) unlink(CACHE_TEMP_SOURCE);
+
+ // Success!
+ return 0;
}