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-rw-r--r--applypatch/applypatch.cpp540
1 files changed, 257 insertions, 283 deletions
diff --git a/applypatch/applypatch.cpp b/applypatch/applypatch.cpp
index 9d505f9f6..5483a68da 100644
--- a/applypatch/applypatch.cpp
+++ b/applypatch/applypatch.cpp
@@ -14,6 +14,8 @@
* limitations under the License.
*/
+#include "applypatch/applypatch.h"
+
#include <errno.h>
#include <fcntl.h>
#include <libgen.h>
@@ -27,16 +29,18 @@
#include <memory>
#include <string>
+#include <utility>
+#include <vector>
+#include <android-base/parseint.h>
#include <android-base/strings.h>
+#include <openssl/sha.h>
-#include "openssl/sha.h"
-#include "applypatch/applypatch.h"
#include "edify/expr.h"
#include "ota_io.h"
#include "print_sha1.h"
-static int LoadPartitionContents(const char* filename, FileContents* file);
+static int LoadPartitionContents(const std::string& filename, FileContents* file);
static ssize_t FileSink(const unsigned char* data, ssize_t len, void* token);
static int GenerateTarget(FileContents* source_file,
const Value* source_patch_value,
@@ -48,39 +52,34 @@ static int GenerateTarget(FileContents* source_file,
size_t target_size,
const Value* bonus_data);
-// Read a file into memory; store the file contents and associated
-// metadata in *file.
-//
+// Read a file into memory; store the file contents and associated metadata in *file.
// Return 0 on success.
int LoadFileContents(const char* filename, FileContents* file) {
- // A special 'filename' beginning with "EMMC:" means to
- // load the contents of a partition.
- if (strncmp(filename, "EMMC:", 5) == 0) {
- return LoadPartitionContents(filename, file);
- }
+ // A special 'filename' beginning with "EMMC:" means to load the contents of a partition.
+ if (strncmp(filename, "EMMC:", 5) == 0) {
+ return LoadPartitionContents(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) == -1) {
+ printf("failed to stat \"%s\": %s\n", filename, strerror(errno));
+ return -1;
+ }
- std::vector<unsigned char> data(file->st.st_size);
- FILE* f = ota_fopen(filename, "rb");
- if (f == NULL) {
- printf("failed to open \"%s\": %s\n", filename, strerror(errno));
- return -1;
- }
+ std::vector<unsigned char> data(file->st.st_size);
+ std::unique_ptr<FILE, decltype(&ota_fclose)> f(ota_fopen(filename, "rb"), ota_fclose);
+ if (!f) {
+ printf("failed to open \"%s\": %s\n", filename, strerror(errno));
+ return -1;
+ }
- size_t bytes_read = ota_fread(data.data(), 1, data.size(), f);
- if (bytes_read != data.size()) {
- printf("short read of \"%s\" (%zu bytes of %zu)\n", filename, bytes_read, data.size());
- ota_fclose(f);
- return -1;
- }
- ota_fclose(f);
- file->data = std::move(data);
- SHA1(file->data.data(), file->data.size(), file->sha1);
- return 0;
+ size_t bytes_read = ota_fread(data.data(), 1, data.size(), f.get());
+ if (bytes_read != data.size()) {
+ printf("short read of \"%s\" (%zu bytes of %zu)\n", filename, bytes_read, data.size());
+ return -1;
+ }
+ file->data = std::move(data);
+ SHA1(file->data.data(), file->data.size(), file->sha1);
+ return 0;
}
// Load the contents of an EMMC partition into the provided
@@ -97,114 +96,98 @@ int LoadFileContents(const char* filename, FileContents* file) {
// "end-of-file" marker), so the caller must specify the possible
// lengths and the hash of the data, and we'll do the load expecting
// to find one of those hashes.
-static int LoadPartitionContents(const char* filename, FileContents* file) {
- std::string copy(filename);
- std::vector<std::string> pieces = android::base::Split(copy, ":");
- if (pieces.size() < 4 || pieces.size() % 2 != 0) {
- printf("LoadPartitionContents called with bad filename (%s)\n", filename);
- return -1;
- }
-
- if (pieces[0] != "EMMC") {
- printf("LoadPartitionContents called with bad filename (%s)\n", filename);
+static int LoadPartitionContents(const std::string& filename, FileContents* file) {
+ std::vector<std::string> pieces = android::base::Split(filename, ":");
+ if (pieces.size() < 4 || pieces.size() % 2 != 0 || pieces[0] != "EMMC") {
+ printf("LoadPartitionContents called with bad filename \"%s\"\n", filename.c_str());
+ return -1;
+ }
+
+ size_t pair_count = (pieces.size() - 2) / 2; // # of (size, sha1) pairs in filename
+ std::vector<std::pair<size_t, std::string>> pairs;
+ for (size_t i = 0; i < pair_count; ++i) {
+ size_t size;
+ if (!android::base::ParseUint(pieces[i * 2 + 2], &size) || size == 0) {
+ printf("LoadPartitionContents called with bad size \"%s\"\n", pieces[i * 2 + 2].c_str());
+ return -1;
+ }
+ pairs.push_back({ size, pieces[i * 2 + 3] });
+ }
+
+ // Sort the pairs array so that they are in order of increasing size.
+ std::sort(pairs.begin(), pairs.end());
+
+ const char* partition = pieces[1].c_str();
+ std::unique_ptr<FILE, decltype(&ota_fclose)> dev(ota_fopen(partition, "rb"), ota_fclose);
+ if (!dev) {
+ printf("failed to open emmc partition \"%s\": %s\n", partition, strerror(errno));
+ return -1;
+ }
+
+ SHA_CTX sha_ctx;
+ SHA1_Init(&sha_ctx);
+
+ // Allocate enough memory to hold the largest size.
+ std::vector<unsigned char> buffer(pairs[pair_count - 1].first);
+ unsigned char* buffer_ptr = buffer.data();
+ size_t buffer_size = 0; // # bytes read so far
+ bool found = false;
+
+ for (const auto& pair : pairs) {
+ size_t current_size = pair.first;
+ const std::string& current_sha1 = pair.second;
+
+ // 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 = current_size - buffer_size;
+ if (next > 0) {
+ size_t read = ota_fread(buffer_ptr, 1, next, dev.get());
+ if (next != read) {
+ printf("short read (%zu bytes of %zu) for partition \"%s\"\n", read, next, partition);
return -1;
- }
- const char* partition = pieces[1].c_str();
-
- size_t pairs = (pieces.size() - 2) / 2; // # of (size, sha1) pairs in filename
- std::vector<size_t> index(pairs);
- std::vector<size_t> size(pairs);
- std::vector<std::string> sha1sum(pairs);
-
- for (size_t i = 0; i < pairs; ++i) {
- size[i] = strtol(pieces[i*2+2].c_str(), NULL, 10);
- if (size[i] == 0) {
- printf("LoadPartitionContents called with bad size (%s)\n", filename);
- return -1;
- }
- sha1sum[i] = pieces[i*2+3].c_str();
- index[i] = i;
+ }
+ SHA1_Update(&sha_ctx, buffer_ptr, read);
+ buffer_size += read;
+ buffer_ptr += read;
}
- // Sort the index[] array so it indexes the pairs in order of increasing size.
- sort(index.begin(), index.end(),
- [&](const size_t& i, const size_t& j) {
- return (size[i] < size[j]);
- }
- );
+ // 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));
+ uint8_t sha_so_far[SHA_DIGEST_LENGTH];
+ SHA1_Final(sha_so_far, &temp_ctx);
- FILE* dev = ota_fopen(partition, "rb");
- if (dev == NULL) {
- printf("failed to open emmc partition \"%s\": %s\n", partition, strerror(errno));
- return -1;
- }
-
- SHA_CTX sha_ctx;
- SHA1_Init(&sha_ctx);
uint8_t parsed_sha[SHA_DIGEST_LENGTH];
-
- // Allocate enough memory to hold the largest size.
- std::vector<unsigned char> data(size[index[pairs-1]]);
- char* p = reinterpret_cast<char*>(data.data());
- size_t data_size = 0; // # bytes read so far
- bool found = false;
-
- for (size_t 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]] - data_size;
- if (next > 0) {
- size_t read = ota_fread(p, 1, next, dev);
- if (next != read) {
- printf("short read (%zu bytes of %zu) for partition \"%s\"\n",
- read, next, partition);
- return -1;
- }
- SHA1_Update(&sha_ctx, p, read);
- data_size += read;
- p += 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));
- uint8_t sha_so_far[SHA_DIGEST_LENGTH];
- SHA1_Final(sha_so_far, &temp_ctx);
-
- if (ParseSha1(sha1sum[index[i]].c_str(), parsed_sha) != 0) {
- printf("failed to parse sha1 %s in %s\n", sha1sum[index[i]].c_str(), filename);
- return -1;
- }
-
- if (memcmp(sha_so_far, parsed_sha, SHA_DIGEST_LENGTH) == 0) {
- // we have a match. stop reading the partition; we'll return
- // the data we've read so far.
- printf("partition read matched size %zu sha %s\n",
- size[index[i]], sha1sum[index[i]].c_str());
- found = true;
- break;
- }
+ if (ParseSha1(current_sha1.c_str(), parsed_sha) != 0) {
+ printf("failed to parse SHA-1 %s in %s\n", current_sha1.c_str(), filename.c_str());
+ return -1;
}
- ota_fclose(dev);
-
- if (!found) {
- // Ran off the end of the list of (size,sha1) pairs without finding a match.
- printf("contents of partition \"%s\" didn't match %s\n", partition, filename);
- return -1;
+ if (memcmp(sha_so_far, parsed_sha, SHA_DIGEST_LENGTH) == 0) {
+ // We have a match. Stop reading the partition; we'll return the data we've read so far.
+ printf("partition read matched size %zu SHA-1 %s\n", current_size, current_sha1.c_str());
+ found = true;
+ break;
}
+ }
- SHA1_Final(file->sha1, &sha_ctx);
+ if (!found) {
+ // Ran off the end of the list of (size, sha1) pairs without finding a match.
+ printf("contents of partition \"%s\" didn't match %s\n", partition, filename.c_str());
+ return -1;
+ }
- data.resize(data_size);
- file->data = std::move(data);
- // Fake some stat() info.
- file->st.st_mode = 0644;
- file->st.st_uid = 0;
- file->st.st_gid = 0;
+ SHA1_Final(file->sha1, &sha_ctx);
- return 0;
+ buffer.resize(buffer_size);
+ file->data = std::move(buffer);
+ // Fake some stat() info.
+ file->st.st_mode = 0644;
+ file->st.st_uid = 0;
+ file->st.st_gid = 0;
+
+ return 0;
}
@@ -250,131 +233,124 @@ int SaveFileContents(const char* filename, const FileContents* file) {
// might contain multiple colons, but WriteToPartition() only uses the first
// two and ignores the rest. Return 0 on success.
int WriteToPartition(const unsigned char* data, size_t len, const char* target) {
- std::string copy(target);
- std::vector<std::string> pieces = android::base::Split(copy, ":");
-
- if (pieces.size() < 2) {
- printf("WriteToPartition called with bad target (%s)\n", target);
- return -1;
- }
-
- if (pieces[0] != "EMMC") {
- printf("WriteToPartition called with bad target (%s)\n", target);
- return -1;
- }
- const char* partition = pieces[1].c_str();
-
- size_t start = 0;
- bool success = false;
- int fd = ota_open(partition, O_RDWR | O_SYNC);
- if (fd < 0) {
- printf("failed to open %s: %s\n", partition, strerror(errno));
- return -1;
- }
-
- for (size_t attempt = 0; attempt < 2; ++attempt) {
- if (TEMP_FAILURE_RETRY(lseek(fd, start, SEEK_SET)) == -1) {
- printf("failed seek on %s: %s\n", partition, strerror(errno));
- return -1;
- }
- while (start < len) {
- size_t to_write = len - start;
- if (to_write > 1<<20) to_write = 1<<20;
-
- ssize_t written = TEMP_FAILURE_RETRY(ota_write(fd, data+start, to_write));
- if (written == -1) {
- printf("failed write writing to %s: %s\n", partition, strerror(errno));
- return -1;
- }
- start += written;
- }
- if (ota_fsync(fd) != 0) {
- printf("failed to sync to %s (%s)\n", partition, strerror(errno));
- return -1;
- }
- if (ota_close(fd) != 0) {
- printf("failed to close %s (%s)\n", partition, strerror(errno));
- return -1;
- }
- fd = ota_open(partition, O_RDONLY);
- if (fd < 0) {
- printf("failed to reopen %s for verify (%s)\n", partition, strerror(errno));
- return -1;
- }
+ std::vector<std::string> pieces = android::base::Split(std::string(target), ":");
- // Drop caches so our subsequent verification read
- // won't just be reading the cache.
- sync();
- int dc = ota_open("/proc/sys/vm/drop_caches", O_WRONLY);
- if (TEMP_FAILURE_RETRY(ota_write(dc, "3\n", 2)) == -1) {
- printf("write to /proc/sys/vm/drop_caches failed: %s\n", strerror(errno));
- } else {
- printf(" caches dropped\n");
- }
- ota_close(dc);
- sleep(1);
-
- // verify
- if (TEMP_FAILURE_RETRY(lseek(fd, 0, SEEK_SET)) == -1) {
- printf("failed to seek back to beginning of %s: %s\n",
- partition, strerror(errno));
- return -1;
- }
- unsigned char buffer[4096];
- start = len;
- for (size_t p = 0; p < len; p += sizeof(buffer)) {
- size_t to_read = len - p;
- if (to_read > sizeof(buffer)) {
- to_read = sizeof(buffer);
- }
+ if (pieces.size() < 2 || pieces[0] != "EMMC") {
+ printf("WriteToPartition called with bad target (%s)\n", target);
+ return -1;
+ }
- size_t so_far = 0;
- while (so_far < to_read) {
- ssize_t read_count =
- TEMP_FAILURE_RETRY(ota_read(fd, buffer+so_far, to_read-so_far));
- if (read_count == -1) {
- printf("verify read error %s at %zu: %s\n",
- partition, p, strerror(errno));
- return -1;
- } else if (read_count == 0) {
- printf("verify read reached unexpected EOF, %s at %zu\n", partition, p);
- return -1;
- }
- if (static_cast<size_t>(read_count) < to_read) {
- printf("short verify read %s at %zu: %zd %zu %s\n",
- partition, p, read_count, to_read, strerror(errno));
- }
- so_far += read_count;
- }
+ const char* partition = pieces[1].c_str();
- if (memcmp(buffer, data+p, to_read) != 0) {
- printf("verification failed starting at %zu\n", p);
- start = p;
- break;
- }
- }
+ size_t start = 0;
+ bool success = false;
+ int fd = ota_open(partition, O_RDWR | O_SYNC);
+ if (fd < 0) {
+ printf("failed to open %s: %s\n", partition, strerror(errno));
+ return -1;
+ }
- if (start == len) {
- printf("verification read succeeded (attempt %zu)\n", attempt+1);
- success = true;
- break;
- }
+ for (size_t attempt = 0; attempt < 2; ++attempt) {
+ if (TEMP_FAILURE_RETRY(lseek(fd, start, SEEK_SET)) == -1) {
+ printf("failed seek on %s: %s\n", partition, strerror(errno));
+ return -1;
}
+ while (start < len) {
+ size_t to_write = len - start;
+ if (to_write > 1 << 20) to_write = 1 << 20;
- if (!success) {
- printf("failed to verify after all attempts\n");
+ ssize_t written = TEMP_FAILURE_RETRY(ota_write(fd, data + start, to_write));
+ if (written == -1) {
+ printf("failed write writing to %s: %s\n", partition, strerror(errno));
return -1;
+ }
+ start += written;
}
+ if (ota_fsync(fd) != 0) {
+ printf("failed to sync to %s (%s)\n", partition, strerror(errno));
+ return -1;
+ }
if (ota_close(fd) != 0) {
- printf("error closing %s (%s)\n", partition, strerror(errno));
- return -1;
+ printf("failed to close %s (%s)\n", partition, strerror(errno));
+ return -1;
}
+
+ fd = ota_open(partition, O_RDONLY);
+ if (fd < 0) {
+ printf("failed to reopen %s for verify (%s)\n", partition, strerror(errno));
+ return -1;
+ }
+
+ // Drop caches so our subsequent verification read won't just be reading the cache.
sync();
+ int dc = ota_open("/proc/sys/vm/drop_caches", O_WRONLY);
+ if (TEMP_FAILURE_RETRY(ota_write(dc, "3\n", 2)) == -1) {
+ printf("write to /proc/sys/vm/drop_caches failed: %s\n", strerror(errno));
+ } else {
+ printf(" caches dropped\n");
+ }
+ ota_close(dc);
+ sleep(1);
+
+ // verify
+ if (TEMP_FAILURE_RETRY(lseek(fd, 0, SEEK_SET)) == -1) {
+ printf("failed to seek back to beginning of %s: %s\n", partition, strerror(errno));
+ return -1;
+ }
+
+ unsigned char buffer[4096];
+ start = len;
+ for (size_t p = 0; p < len; p += sizeof(buffer)) {
+ size_t to_read = len - p;
+ if (to_read > sizeof(buffer)) {
+ to_read = sizeof(buffer);
+ }
+
+ size_t so_far = 0;
+ while (so_far < to_read) {
+ ssize_t read_count = TEMP_FAILURE_RETRY(ota_read(fd, buffer + so_far, to_read - so_far));
+ if (read_count == -1) {
+ printf("verify read error %s at %zu: %s\n", partition, p, strerror(errno));
+ return -1;
+ } else if (read_count == 0) {
+ printf("verify read reached unexpected EOF, %s at %zu\n", partition, p);
+ return -1;
+ }
+ if (static_cast<size_t>(read_count) < to_read) {
+ printf("short verify read %s at %zu: %zd %zu %s\n", partition, p, read_count, to_read,
+ strerror(errno));
+ }
+ so_far += read_count;
+ }
+
+ if (memcmp(buffer, data + p, to_read) != 0) {
+ printf("verification failed starting at %zu\n", p);
+ start = p;
+ break;
+ }
+ }
+
+ if (start == len) {
+ printf("verification read succeeded (attempt %zu)\n", attempt + 1);
+ success = true;
+ break;
+ }
+ }
+
+ if (!success) {
+ printf("failed to verify after all attempts\n");
+ return -1;
+ }
- return 0;
-}
+ if (ota_close(fd) != 0) {
+ printf("error closing %s (%s)\n", partition, strerror(errno));
+ return -1;
+ }
+ sync();
+ return 0;
+}
// Take a string 'str' of 40 hex digits and parse it into the 20
// byte array 'digest'. 'str' may contain only the digest or be of
@@ -409,48 +385,46 @@ int ParseSha1(const char* str, uint8_t* digest) {
// Return the index of the match on success, or -1 if no match is
// found.
int FindMatchingPatch(uint8_t* sha1, const std::vector<std::string>& patch_sha1_str) {
- for (size_t i = 0; i < patch_sha1_str.size(); ++i) {
- uint8_t patch_sha1[SHA_DIGEST_LENGTH];
- if (ParseSha1(patch_sha1_str[i].c_str(), patch_sha1) == 0 &&
- memcmp(patch_sha1, sha1, SHA_DIGEST_LENGTH) == 0) {
- return i;
- }
- }
- return -1;
+ for (size_t i = 0; i < patch_sha1_str.size(); ++i) {
+ uint8_t patch_sha1[SHA_DIGEST_LENGTH];
+ if (ParseSha1(patch_sha1_str[i].c_str(), patch_sha1) == 0 &&
+ memcmp(patch_sha1, sha1, SHA_DIGEST_LENGTH) == 0) {
+ return i;
+ }
+ }
+ 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 applypatch_check(const char* filename, const std::vector<std::string>& patch_sha1_str) {
- FileContents file;
-
- // It's okay to specify no sha1s; the check will pass if the
- // LoadFileContents is successful. (Useful for reading
- // partitions, where the filename encodes the sha1s; no need to
- // check them twice.)
- if (LoadFileContents(filename, &file) != 0 ||
- (patch_sha1_str.size() > 0 && FindMatchingPatch(file.sha1, patch_sha1_str) < 0)) {
- printf("file \"%s\" doesn't have any of expected "
- "sha1 sums; checking cache\n", filename);
-
- // 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, patch_sha1_str) < 0) {
- printf("cache bits don't match any sha1 for \"%s\"\n", filename);
- return 1;
- }
- }
- return 0;
+ FileContents file;
+
+ // It's okay to specify no sha1s; the check will pass if the
+ // LoadFileContents is successful. (Useful for reading
+ // partitions, where the filename encodes the sha1s; no need to
+ // check them twice.)
+ if (LoadFileContents(filename, &file) != 0 ||
+ (!patch_sha1_str.empty() && FindMatchingPatch(file.sha1, patch_sha1_str) < 0)) {
+ printf("file \"%s\" doesn't have any of expected sha1 sums; checking cache\n", filename);
+
+ // 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, patch_sha1_str) < 0) {
+ printf("cache bits don't match any sha1 for \"%s\"\n", filename);
+ return 1;
+ }
+ }
+ return 0;
}
int ShowLicenses() {
@@ -544,10 +518,8 @@ int applypatch(const char* source_filename,
return 1;
}
- FileContents copy_file;
FileContents source_file;
const Value* source_patch_value = nullptr;
- const Value* copy_patch_value = nullptr;
// We try to load the target file into the source_file object.
if (LoadFileContents(target_filename, &source_file) == 0) {
@@ -575,6 +547,8 @@ int applypatch(const char* source_filename,
}
}
+ FileContents copy_file;
+ const Value* copy_patch_value = nullptr;
if (source_patch_value == nullptr) {
source_file.data.clear();
printf("source file is bad; trying copy\n");
@@ -620,7 +594,6 @@ int applypatch_flash(const char* source_filename, const char* target_filename,
return 1;
}
- FileContents source_file;
std::string target_str(target_filename);
std::vector<std::string> pieces = android::base::Split(target_str, ":");
@@ -633,12 +606,13 @@ int applypatch_flash(const char* source_filename, const char* target_filename,
pieces.push_back(std::to_string(target_size));
pieces.push_back(target_sha1_str);
std::string fullname = android::base::Join(pieces, ':');
- if (LoadPartitionContents(fullname.c_str(), &source_file) == 0 &&
+ FileContents source_file;
+ if (LoadPartitionContents(fullname, &source_file) == 0 &&
memcmp(source_file.sha1, target_sha1, SHA_DIGEST_LENGTH) == 0) {
- // The early-exit case: the image was already applied, this partition
- // has the desired hash, nothing for us to do.
- printf("already %s\n", short_sha1(target_sha1).c_str());
- return 0;
+ // The early-exit case: the image was already applied, this partition
+ // has the desired hash, nothing for us to do.
+ printf("already %s\n", short_sha1(target_sha1).c_str());
+ return 0;
}
if (LoadFileContents(source_filename, &source_file) == 0) {