diff --git a/applypatch/Android.mk b/applypatch/Android.mk
index 2215194..23d0f7b 100644
--- a/applypatch/Android.mk
+++ b/applypatch/Android.mk
@@ -55,7 +55,7 @@
 LOCAL_SRC_FILES := main.cpp
 LOCAL_MODULE := applypatch
 LOCAL_C_INCLUDES += bootable/recovery
-LOCAL_STATIC_LIBRARIES += libapplypatch libbase libmtdutils libcrypto_static libbz
+LOCAL_STATIC_LIBRARIES += libapplypatch libbase libmtdutils libcrypto_static libbz libedify
 LOCAL_SHARED_LIBRARIES += libz libcutils libc
 
 include $(BUILD_EXECUTABLE)
diff --git a/applypatch/applypatch.cpp b/applypatch/applypatch.cpp
index 75ffe0f..75d7737 100644
--- a/applypatch/applypatch.cpp
+++ b/applypatch/applypatch.cpp
@@ -25,6 +25,9 @@
 #include <sys/types.h>
 #include <unistd.h>
 
+#include <memory>
+#include <string>
+
 #include <android-base/strings.h>
 
 #include "openssl/sha.h"
@@ -67,25 +70,29 @@
     }
 
     file->size = file->st.st_size;
-    file->data = reinterpret_cast<unsigned char*>(malloc(file->size));
+    file->data = nullptr;
+
+    std::unique_ptr<unsigned char, decltype(&free)> data(
+            static_cast<unsigned char*>(malloc(file->size)), free);
+    if (data == nullptr) {
+        printf("failed to allocate memory: %s\n", strerror(errno));
+        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);
+    size_t bytes_read = fread(data.get(), 1, file->size, f);
     if (bytes_read != static_cast<size_t>(file->size)) {
         printf("short read of \"%s\" (%zu bytes of %zd)\n", filename, bytes_read, file->size);
-        free(file->data);
-        file->data = NULL;
+        fclose(f);
         return -1;
     }
     fclose(f);
-
+    file->data = data.release();
     SHA1(file->data, file->size, file->sha1);
     return 0;
 }
@@ -185,7 +192,7 @@
     uint8_t parsed_sha[SHA_DIGEST_LENGTH];
 
     // Allocate enough memory to hold the largest size.
-    file->data = reinterpret_cast<unsigned char*>(malloc(size[index[pairs-1]]));
+    file->data = static_cast<unsigned char*>(malloc(size[index[pairs-1]]));
     char* p = (char*)file->data;
     file->size = 0;                // # bytes read so far
     bool found = false;
@@ -313,7 +320,7 @@
 // "MTD:<partition>[:...]" or "EMMC:<partition_device>[:...]". The target name
 // might contain multiple colons, but WriteToPartition() only uses the first
 // two and ignores the rest. Return 0 on success.
-int WriteToPartition(unsigned char* data, size_t len, const char* target) {
+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, ":");
 
@@ -352,7 +359,7 @@
                 return -1;
             }
 
-            size_t written = mtd_write_data(ctx, reinterpret_cast<char*>(data), len);
+            size_t written = mtd_write_data(ctx, reinterpret_cast<const char*>(data), len);
             if (written != len) {
                 printf("only wrote %zu of %zu bytes to MTD %s\n", written, len, partition);
                 mtd_write_close(ctx);
@@ -578,7 +585,7 @@
 }
 
 ssize_t FileSink(const unsigned char* data, ssize_t len, void* token) {
-    int fd = *reinterpret_cast<int *>(token);
+    int fd = *static_cast<int*>(token);
     ssize_t done = 0;
     ssize_t wrote;
     while (done < len) {
@@ -592,19 +599,9 @@
     return done;
 }
 
-typedef struct {
-    unsigned char* buffer;
-    ssize_t size;
-    ssize_t pos;
-} MemorySinkInfo;
-
 ssize_t MemorySink(const unsigned char* data, ssize_t len, void* token) {
-    MemorySinkInfo* msi = reinterpret_cast<MemorySinkInfo*>(token);
-    if (msi->size - msi->pos < len) {
-        return -1;
-    }
-    memcpy(msi->buffer + msi->pos, data, len);
-    msi->pos += len;
+    std::string* s = static_cast<std::string*>(token);
+    s->append(reinterpret_cast<const char*>(data), len);
     return len;
 }
 
@@ -815,31 +812,52 @@
                           const Value* bonus_data) {
     int retry = 1;
     SHA_CTX ctx;
-    int output;
-    MemorySinkInfo msi;
+    std::string memory_sink_str;
     FileContents* source_to_use;
-    char* outname;
     int made_copy = 0;
 
+    bool target_is_partition = (strncmp(target_filename, "MTD:", 4) == 0 ||
+                                strncmp(target_filename, "EMMC:", 5) == 0);
+    const std::string tmp_target_filename = std::string(target_filename) + ".patch";
+
     // 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';
+    std::string target_fs = target_filename;
+    auto slash_pos = target_fs.find('/', 1);
+    if (slash_pos != std::string::npos) {
+        target_fs.resize(slash_pos);
+    }
+
+    const Value* patch;
+    if (source_patch_value != NULL) {
+        source_to_use = source_file;
+        patch = source_patch_value;
     } else {
-        strcpy(target_fs, target_filename);
+        source_to_use = copy_file;
+        patch = copy_patch_value;
+    }
+    if (patch->type != VAL_BLOB) {
+        printf("patch is not a blob\n");
+        return 1;
+    }
+    char* header = patch->data;
+    ssize_t header_bytes_read = patch->size;
+    bool use_bsdiff = false;
+    if (header_bytes_read >= 8 && memcmp(header, "BSDIFF40", 8) == 0) {
+        use_bsdiff = true;
+    } else if (header_bytes_read >= 8 && memcmp(header, "IMGDIFF2", 8) == 0) {
+        use_bsdiff = false;
+    } else {
+        printf("Unknown patch file format\n");
+        return 1;
     }
 
     do {
         // Is there enough room in the target filesystem to hold the patched
         // file?
 
-        if (strncmp(target_filename, "MTD:", 4) == 0 ||
-            strncmp(target_filename, "EMMC:", 5) == 0) {
+        if (target_is_partition) {
             // If the target is a 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
@@ -861,7 +879,7 @@
         } else {
             int enough_space = 0;
             if (retry > 0) {
-                size_t free_space = FreeSpaceForFile(target_fs);
+                size_t free_space = FreeSpaceForFile(target_fs.c_str());
                 enough_space =
                     (free_space > (256 << 10)) &&          // 256k (two-block) minimum
                     (free_space > (target_size * 3 / 2));  // 50% margin of error
@@ -901,84 +919,53 @@
                 made_copy = 1;
                 unlink(source_filename);
 
-                size_t free_space = FreeSpaceForFile(target_fs);
+                size_t free_space = FreeSpaceForFile(target_fs.c_str());
                 printf("(now %zu bytes free for target) ", 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 ||
-            strncmp(target_filename, "EMMC:", 5) == 0) {
+        int output_fd = -1;
+        if (target_is_partition) {
             // We store the decoded output in memory.
-            msi.buffer = reinterpret_cast<unsigned char*>(malloc(target_size));
-            if (msi.buffer == NULL) {
-                printf("failed to alloc %zu bytes for output\n", target_size);
-                return 1;
-            }
-            msi.pos = 0;
-            msi.size = target_size;
             sink = MemorySink;
-            token = &msi;
+            token = &memory_sink_str;
         } else {
             // We write the decoded output to "<tgt-file>.patch".
-            outname = reinterpret_cast<char*>(malloc(strlen(target_filename) + 10));
-            strcpy(outname, target_filename);
-            strcat(outname, ".patch");
-
-            output = open(outname, O_WRONLY | O_CREAT | O_TRUNC | O_SYNC, S_IRUSR | S_IWUSR);
-            if (output < 0) {
-                printf("failed to open output file %s: %s\n",
-                       outname, strerror(errno));
+            output_fd = open(tmp_target_filename.c_str(), O_WRONLY | O_CREAT | O_TRUNC | O_SYNC,
+                          S_IRUSR | S_IWUSR);
+            if (output_fd < 0) {
+                printf("failed to open output file %s: %s\n", tmp_target_filename.c_str(),
+                       strerror(errno));
                 return 1;
             }
             sink = FileSink;
-            token = &output;
+            token = &output_fd;
         }
 
-        char* header = patch->data;
-        ssize_t header_bytes_read = patch->size;
 
         SHA1_Init(&ctx);
 
         int result;
-
-        if (header_bytes_read >= 8 &&
-            memcmp(header, "BSDIFF40", 8) == 0) {
+        if (use_bsdiff) {
             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) {
+        } else {
             result = ApplyImagePatch(source_to_use->data, source_to_use->size,
                                      patch, sink, token, &ctx, bonus_data);
-        } else {
-            printf("Unknown patch file format\n");
-            return 1;
         }
 
-        if (output >= 0) {
-            if (fsync(output) != 0) {
-                printf("failed to fsync file \"%s\" (%s)\n", outname, strerror(errno));
+        if (!target_is_partition) {
+            if (fsync(output_fd) != 0) {
+                printf("failed to fsync file \"%s\" (%s)\n", tmp_target_filename.c_str(),
+                       strerror(errno));
                 result = 1;
             }
-            if (close(output) != 0) {
-                printf("failed to close file \"%s\" (%s)\n", outname, strerror(errno));
+            if (close(output_fd) != 0) {
+                printf("failed to close file \"%s\" (%s)\n", tmp_target_filename.c_str(),
+                       strerror(errno));
                 result = 1;
             }
         }
@@ -990,8 +977,8 @@
             } else {
                 printf("applying patch failed; retrying\n");
             }
-            if (outname != NULL) {
-                unlink(outname);
+            if (!target_is_partition) {
+                unlink(tmp_target_filename.c_str());
             }
         } else {
             // succeeded; no need to retry
@@ -1008,27 +995,27 @@
         printf("now %s\n", short_sha1(target_sha1).c_str());
     }
 
-    if (output < 0) {
+    if (target_is_partition) {
         // Copy the temp file to the partition.
-        if (WriteToPartition(msi.buffer, msi.pos, target_filename) != 0) {
+        if (WriteToPartition(reinterpret_cast<const unsigned char*>(memory_sink_str.c_str()),
+                             memory_sink_str.size(), 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));
+        if (chmod(tmp_target_filename.c_str(), source_to_use->st.st_mode) != 0) {
+            printf("chmod of \"%s\" failed: %s\n", tmp_target_filename.c_str(), 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));
+        if (chown(tmp_target_filename.c_str(), source_to_use->st.st_uid, source_to_use->st.st_gid) != 0) {
+            printf("chown of \"%s\" failed: %s\n", tmp_target_filename.c_str(), strerror(errno));
             return 1;
         }
 
         // Finally, rename the .patch file to replace the target file.
-        if (rename(outname, target_filename) != 0) {
+        if (rename(tmp_target_filename.c_str(), target_filename) != 0) {
             printf("rename of .patch to \"%s\" failed: %s\n", target_filename, strerror(errno));
             return 1;
         }
diff --git a/applypatch/applypatch.h b/applypatch/applypatch.h
index e0df104..14fb490 100644
--- a/applypatch/applypatch.h
+++ b/applypatch/applypatch.h
@@ -18,6 +18,9 @@
 #define _APPLYPATCH_H
 
 #include <sys/stat.h>
+
+#include <vector>
+
 #include "openssl/sha.h"
 #include "edify/expr.h"
 
@@ -68,22 +71,22 @@
 int FindMatchingPatch(uint8_t* sha1, char* const * const patch_sha1_str,
                       int num_patches);
 
-// bsdiff.c
+// bsdiff.cpp
 void ShowBSDiffLicense();
 int ApplyBSDiffPatch(const unsigned char* old_data, ssize_t old_size,
                      const Value* patch, ssize_t patch_offset,
                      SinkFn sink, void* token, SHA_CTX* ctx);
 int ApplyBSDiffPatchMem(const unsigned char* old_data, ssize_t old_size,
                         const Value* patch, ssize_t patch_offset,
-                        unsigned char** new_data, ssize_t* new_size);
+                        std::vector<unsigned char>* new_data);
 
-// imgpatch.c
+// imgpatch.cpp
 int ApplyImagePatch(const unsigned char* old_data, ssize_t old_size,
                     const Value* patch,
                     SinkFn sink, void* token, SHA_CTX* ctx,
                     const Value* bonus_data);
 
-// freecache.c
+// freecache.cpp
 int MakeFreeSpaceOnCache(size_t bytes_needed);
 
 #endif
diff --git a/applypatch/bspatch.cpp b/applypatch/bspatch.cpp
index 2517117..ebb55f1 100644
--- a/applypatch/bspatch.cpp
+++ b/applypatch/bspatch.cpp
@@ -24,7 +24,6 @@
 #include <sys/stat.h>
 #include <sys/types.h>
 #include <errno.h>
-#include <malloc.h>
 #include <unistd.h>
 #include <string.h>
 
@@ -103,26 +102,22 @@
                      const Value* patch, ssize_t patch_offset,
                      SinkFn sink, void* token, SHA_CTX* ctx) {
 
-    unsigned char* new_data;
-    ssize_t new_size;
-    if (ApplyBSDiffPatchMem(old_data, old_size, patch, patch_offset,
-                            &new_data, &new_size) != 0) {
+    std::vector<unsigned char> new_data;
+    if (ApplyBSDiffPatchMem(old_data, old_size, patch, patch_offset, &new_data) != 0) {
         return -1;
     }
 
-    if (sink(new_data, new_size, token) < new_size) {
+    if (sink(new_data.data(), new_data.size(), token) < static_cast<ssize_t>(new_data.size())) {
         printf("short write of output: %d (%s)\n", errno, strerror(errno));
         return 1;
     }
-    if (ctx) SHA1_Update(ctx, new_data, new_size);
-    free(new_data);
-
+    if (ctx) SHA1_Update(ctx, new_data.data(), new_data.size());
     return 0;
 }
 
 int ApplyBSDiffPatchMem(const unsigned char* old_data, ssize_t old_size,
                         const Value* patch, ssize_t patch_offset,
-                        unsigned char** new_data, ssize_t* new_size) {
+                        std::vector<unsigned char>* new_data) {
     // Patch data format:
     //   0       8       "BSDIFF40"
     //   8       8       X
@@ -141,12 +136,12 @@
         return 1;
     }
 
-    ssize_t ctrl_len, data_len;
+    ssize_t ctrl_len, data_len, new_size;
     ctrl_len = offtin(header+8);
     data_len = offtin(header+16);
-    *new_size = offtin(header+24);
+    new_size = offtin(header+24);
 
-    if (ctrl_len < 0 || data_len < 0 || *new_size < 0) {
+    if (ctrl_len < 0 || data_len < 0 || new_size < 0) {
         printf("corrupt patch file header (data lengths)\n");
         return 1;
     }
@@ -183,18 +178,14 @@
         printf("failed to bzinit extra stream (%d)\n", bzerr);
     }
 
-    *new_data = reinterpret_cast<unsigned char*>(malloc(*new_size));
-    if (*new_data == NULL) {
-        printf("failed to allocate %zd bytes of memory for output file\n", *new_size);
-        return 1;
-    }
+    new_data->resize(new_size);
 
     off_t oldpos = 0, newpos = 0;
     off_t ctrl[3];
     off_t len_read;
     int i;
     unsigned char buf[24];
-    while (newpos < *new_size) {
+    while (newpos < new_size) {
         // Read control data
         if (FillBuffer(buf, 24, &cstream) != 0) {
             printf("error while reading control stream\n");
@@ -210,13 +201,13 @@
         }
 
         // Sanity check
-        if (newpos + ctrl[0] > *new_size) {
+        if (newpos + ctrl[0] > new_size) {
             printf("corrupt patch (new file overrun)\n");
             return 1;
         }
 
         // Read diff string
-        if (FillBuffer(*new_data + newpos, ctrl[0], &dstream) != 0) {
+        if (FillBuffer(new_data->data() + newpos, ctrl[0], &dstream) != 0) {
             printf("error while reading diff stream\n");
             return 1;
         }
@@ -233,13 +224,13 @@
         oldpos += ctrl[0];
 
         // Sanity check
-        if (newpos + ctrl[1] > *new_size) {
+        if (newpos + ctrl[1] > new_size) {
             printf("corrupt patch (new file overrun)\n");
             return 1;
         }
 
         // Read extra string
-        if (FillBuffer(*new_data + newpos, ctrl[1], &estream) != 0) {
+        if (FillBuffer(new_data->data() + newpos, ctrl[1], &estream) != 0) {
             printf("error while reading extra stream\n");
             return 1;
         }
diff --git a/applypatch/freecache.cpp b/applypatch/freecache.cpp
index 2eb2f55..c84f427 100644
--- a/applypatch/freecache.cpp
+++ b/applypatch/freecache.cpp
@@ -25,119 +25,90 @@
 #include <dirent.h>
 #include <ctype.h>
 
+#include <memory>
+#include <set>
+#include <string>
+
+#include <android-base/parseint.h>
+#include <android-base/stringprintf.h>
+
 #include "applypatch.h"
 
-static int EliminateOpenFiles(char** files, int file_count) {
-  DIR* d;
-  struct dirent* de;
-  d = opendir("/proc");
-  if (d == NULL) {
+static int EliminateOpenFiles(std::set<std::string>* files) {
+  std::unique_ptr<DIR, decltype(&closedir)> d(opendir("/proc"), closedir);
+  if (!d) {
     printf("error opening /proc: %s\n", strerror(errno));
     return -1;
   }
-  while ((de = readdir(d)) != 0) {
-    int i;
-    for (i = 0; de->d_name[i] != '\0' && isdigit(de->d_name[i]); ++i);
-    if (de->d_name[i]) continue;
+  struct dirent* de;
+  while ((de = readdir(d.get())) != 0) {
+    unsigned int pid;
+    if (!android::base::ParseUint(de->d_name, &pid)) {
+        continue;
+    }
+    std::string path = android::base::StringPrintf("/proc/%s/fd/", de->d_name);
 
-    // de->d_name[i] is numeric
-
-    char path[FILENAME_MAX];
-    strcpy(path, "/proc/");
-    strcat(path, de->d_name);
-    strcat(path, "/fd/");
-
-    DIR* fdd;
     struct dirent* fdde;
-    fdd = opendir(path);
-    if (fdd == NULL) {
-      printf("error opening %s: %s\n", path, strerror(errno));
+    std::unique_ptr<DIR, decltype(&closedir)> fdd(opendir(path.c_str()), closedir);
+    if (!fdd) {
+      printf("error opening %s: %s\n", path.c_str(), strerror(errno));
       continue;
     }
-    while ((fdde = readdir(fdd)) != 0) {
-      char fd_path[FILENAME_MAX];
+    while ((fdde = readdir(fdd.get())) != 0) {
+      std::string fd_path = path + fdde->d_name;
       char link[FILENAME_MAX];
-      strcpy(fd_path, path);
-      strcat(fd_path, fdde->d_name);
 
-      int count;
-      count = readlink(fd_path, link, sizeof(link)-1);
+      int count = readlink(fd_path.c_str(), link, sizeof(link)-1);
       if (count >= 0) {
         link[count] = '\0';
-
-        // This is inefficient, but it should only matter if there are
-        // lots of files in /cache, and lots of them are open (neither
-        // of which should be true, especially in recovery).
         if (strncmp(link, "/cache/", 7) == 0) {
-          int j;
-          for (j = 0; j < file_count; ++j) {
-            if (files[j] && strcmp(files[j], link) == 0) {
-              printf("%s is open by %s\n", link, de->d_name);
-              free(files[j]);
-              files[j] = NULL;
-            }
+          if (files->erase(link) > 0) {
+            printf("%s is open by %s\n", link, de->d_name);
           }
         }
       }
     }
-    closedir(fdd);
   }
-  closedir(d);
-
   return 0;
 }
 
-int FindExpendableFiles(char*** names, int* entries) {
-  DIR* d;
-  struct dirent* de;
-  int size = 32;
-  *entries = 0;
-  *names = reinterpret_cast<char**>(malloc(size * sizeof(char*)));
-
-  char path[FILENAME_MAX];
-
+static std::set<std::string> FindExpendableFiles() {
+  std::set<std::string> files;
   // We're allowed to delete unopened regular files in any of these
   // directories.
   const char* dirs[2] = {"/cache", "/cache/recovery/otatest"};
 
   for (size_t i = 0; i < sizeof(dirs)/sizeof(dirs[0]); ++i) {
-    d = opendir(dirs[i]);
-    if (d == NULL) {
+    std::unique_ptr<DIR, decltype(&closedir)> d(opendir(dirs[i]), closedir);
+    if (!d) {
       printf("error opening %s: %s\n", dirs[i], strerror(errno));
       continue;
     }
 
     // Look for regular files in the directory (not in any subdirectories).
-    while ((de = readdir(d)) != 0) {
-      strcpy(path, dirs[i]);
-      strcat(path, "/");
-      strcat(path, de->d_name);
+    struct dirent* de;
+    while ((de = readdir(d.get())) != 0) {
+      std::string path = std::string(dirs[i]) + "/" + de->d_name;
 
       // We can't delete CACHE_TEMP_SOURCE; if it's there we might have
       // restarted during installation and could be depending on it to
       // be there.
-      if (strcmp(path, CACHE_TEMP_SOURCE) == 0) continue;
+      if (path == CACHE_TEMP_SOURCE) {
+        continue;
+      }
 
       struct stat st;
-      if (stat(path, &st) == 0 && S_ISREG(st.st_mode)) {
-        if (*entries >= size) {
-          size *= 2;
-          *names = reinterpret_cast<char**>(realloc(*names, size * sizeof(char*)));
-        }
-        (*names)[(*entries)++] = strdup(path);
+      if (stat(path.c_str(), &st) == 0 && S_ISREG(st.st_mode)) {
+        files.insert(path);
       }
     }
-
-    closedir(d);
   }
 
-  printf("%d regular files in deletable directories\n", *entries);
-
-  if (EliminateOpenFiles(*names, *entries) < 0) {
-    return -1;
+  printf("%zu regular files in deletable directories\n", files.size());
+  if (EliminateOpenFiles(&files) < 0) {
+    return std::set<std::string>();
   }
-
-  return 0;
+  return files;
 }
 
 int MakeFreeSpaceOnCache(size_t bytes_needed) {
@@ -147,15 +118,8 @@
   if (free_now >= bytes_needed) {
     return 0;
   }
-
-  char** names;
-  int entries;
-
-  if (FindExpendableFiles(&names, &entries) < 0) {
-    return -1;
-  }
-
-  if (entries == 0) {
+  std::set<std::string> files = FindExpendableFiles();
+  if (files.empty()) {
     // nothing we can delete to free up space!
     printf("no files can be deleted to free space on /cache\n");
     return -1;
@@ -167,20 +131,13 @@
   //
   // Instead, we'll be dumb.
 
-  int i;
-  for (i = 0; i < entries && free_now < bytes_needed; ++i) {
-    if (names[i]) {
-      unlink(names[i]);
-      free_now = FreeSpaceForFile("/cache");
-      printf("deleted %s; now %zu bytes free\n", names[i], free_now);
-      free(names[i]);
+  for (const auto& file : files) {
+    unlink(file.c_str());
+    free_now = FreeSpaceForFile("/cache");
+    printf("deleted %s; now %zu bytes free\n", file.c_str(), free_now);
+    if (free_now < bytes_needed) {
+        break;
     }
   }
-
-  for (; i < entries; ++i) {
-    free(names[i]);
-  }
-  free(names);
-
   return (free_now >= bytes_needed) ? 0 : -1;
 }
diff --git a/applypatch/imgpatch.cpp b/applypatch/imgpatch.cpp
index c9944df..8824038 100644
--- a/applypatch/imgpatch.cpp
+++ b/applypatch/imgpatch.cpp
@@ -21,10 +21,11 @@
 #include <sys/cdefs.h>
 #include <sys/stat.h>
 #include <errno.h>
-#include <malloc.h>
 #include <unistd.h>
 #include <string.h>
 
+#include <vector>
+
 #include "zlib.h"
 #include "openssl/sha.h"
 #include "applypatch.h"
@@ -129,7 +130,6 @@
             size_t src_len = Read8(deflate_header+8);
             size_t patch_offset = Read8(deflate_header+16);
             size_t expanded_len = Read8(deflate_header+24);
-            size_t target_len = Read8(deflate_header+32);
             int level = Read4(deflate_header+40);
             int method = Read4(deflate_header+44);
             int windowBits = Read4(deflate_header+48);
@@ -150,13 +150,7 @@
             // must be appended from the bonus_data value.
             size_t bonus_size = (i == 1 && bonus_data != NULL) ? bonus_data->size : 0;
 
-            unsigned char* expanded_source = reinterpret_cast<unsigned char*>(malloc(expanded_len));
-            if (expanded_source == NULL) {
-                printf("failed to allocate %zu bytes for expanded_source\n",
-                       expanded_len);
-                return -1;
-            }
-
+            std::vector<unsigned char> expanded_source(expanded_len);
             z_stream strm;
             strm.zalloc = Z_NULL;
             strm.zfree = Z_NULL;
@@ -164,7 +158,7 @@
             strm.avail_in = src_len;
             strm.next_in = (unsigned char*)(old_data + src_start);
             strm.avail_out = expanded_len;
-            strm.next_out = expanded_source;
+            strm.next_out = expanded_source.data();
 
             int ret;
             ret = inflateInit2(&strm, -15);
@@ -189,18 +183,16 @@
             inflateEnd(&strm);
 
             if (bonus_size) {
-                memcpy(expanded_source + (expanded_len - bonus_size),
+                memcpy(expanded_source.data() + (expanded_len - bonus_size),
                        bonus_data->data, bonus_size);
             }
 
             // Next, apply the bsdiff patch (in memory) to the uncompressed
             // data.
-            unsigned char* uncompressed_target_data;
-            ssize_t uncompressed_target_size;
-            if (ApplyBSDiffPatchMem(expanded_source, expanded_len,
+            std::vector<unsigned char> uncompressed_target_data;
+            if (ApplyBSDiffPatchMem(expanded_source.data(), expanded_len,
                                     patch, patch_offset,
-                                    &uncompressed_target_data,
-                                    &uncompressed_target_size) != 0) {
+                                    &uncompressed_target_data) != 0) {
                 return -1;
             }
 
@@ -208,40 +200,36 @@
 
             // we're done with the expanded_source data buffer, so we'll
             // reuse that memory to receive the output of deflate.
-            unsigned char* temp_data = expanded_source;
-            ssize_t temp_size = expanded_len;
-            if (temp_size < 32768) {
-                // ... unless the buffer is too small, in which case we'll
-                // allocate a fresh one.
-                free(temp_data);
-                temp_data = reinterpret_cast<unsigned char*>(malloc(32768));
-                temp_size = 32768;
+            if (expanded_source.size() < 32768U) {
+                expanded_source.resize(32768U);
             }
+            std::vector<unsigned char>& temp_data = expanded_source;
 
             // now the deflate stream
             strm.zalloc = Z_NULL;
             strm.zfree = Z_NULL;
             strm.opaque = Z_NULL;
-            strm.avail_in = uncompressed_target_size;
-            strm.next_in = uncompressed_target_data;
+            strm.avail_in = uncompressed_target_data.size();
+            strm.next_in = uncompressed_target_data.data();
             ret = deflateInit2(&strm, level, method, windowBits, memLevel, strategy);
+            if (ret != Z_OK) {
+                printf("failed to init uncompressed data deflation: %d\n", ret);
+                return -1;
+            }
             do {
-                strm.avail_out = temp_size;
-                strm.next_out = temp_data;
+                strm.avail_out = temp_data.size();
+                strm.next_out = temp_data.data();
                 ret = deflate(&strm, Z_FINISH);
-                ssize_t have = temp_size - strm.avail_out;
+                ssize_t have = temp_data.size() - strm.avail_out;
 
-                if (sink(temp_data, have, token) != have) {
+                if (sink(temp_data.data(), have, token) != have) {
                     printf("failed to write %ld compressed bytes to output\n",
                            (long)have);
                     return -1;
                 }
-                if (ctx) SHA1_Update(ctx, temp_data, have);
+                if (ctx) SHA1_Update(ctx, temp_data.data(), have);
             } while (ret != Z_STREAM_END);
             deflateEnd(&strm);
-
-            free(temp_data);
-            free(uncompressed_target_data);
         } else {
             printf("patch chunk %d is unknown type %d\n", i, type);
             return -1;
diff --git a/applypatch/main.cpp b/applypatch/main.cpp
index 445a7fe..7606d5d 100644
--- a/applypatch/main.cpp
+++ b/applypatch/main.cpp
@@ -19,6 +19,9 @@
 #include <string.h>
 #include <unistd.h>
 
+#include <memory>
+#include <vector>
+
 #include "applypatch.h"
 #include "edify/expr.h"
 #include "openssl/sha.h"
@@ -47,16 +50,11 @@
 // "<sha1>:<filename>" into the new parallel arrays *sha1s and
 // *patches (loading file contents into the patches).  Returns true on
 // success.
-static bool ParsePatchArgs(int argc, char** argv, char*** sha1s,
-                           Value*** patches, int* num_patches) {
-    *num_patches = argc;
-    *sha1s = reinterpret_cast<char**>(malloc(*num_patches * sizeof(char*)));
-    *patches = reinterpret_cast<Value**>(malloc(*num_patches * sizeof(Value*)));
-    memset(*patches, 0, *num_patches * sizeof(Value*));
-
+static bool ParsePatchArgs(int argc, char** argv, std::vector<char*>* sha1s,
+                           std::vector<std::unique_ptr<Value, decltype(&FreeValue)>>* patches) {
     uint8_t digest[SHA_DIGEST_LENGTH];
 
-    for (int i = 0; i < *num_patches; ++i) {
+    for (int i = 0; i < argc; ++i) {
         char* colon = strchr(argv[i], ':');
         if (colon != NULL) {
             *colon = '\0';
@@ -68,34 +66,22 @@
             return false;
         }
 
-        (*sha1s)[i] = argv[i];
+        sha1s->push_back(argv[i]);
         if (colon == NULL) {
-            (*patches)[i] = NULL;
+            patches->emplace_back(nullptr, FreeValue);
         } else {
             FileContents fc;
             if (LoadFileContents(colon, &fc) != 0) {
-                goto abort;
+                return false;
             }
-            (*patches)[i] = reinterpret_cast<Value*>(malloc(sizeof(Value)));
-            (*patches)[i]->type = VAL_BLOB;
-            (*patches)[i]->size = fc.size;
-            (*patches)[i]->data = reinterpret_cast<char*>(fc.data);
+            std::unique_ptr<Value, decltype(&FreeValue)> value(new Value, FreeValue);
+            value->type = VAL_BLOB;
+            value->size = fc.size;
+            value->data = reinterpret_cast<char*>(fc.data);
+            patches->push_back(std::move(value));
         }
     }
-
     return true;
-
-  abort:
-    for (int i = 0; i < *num_patches; ++i) {
-        Value* p = (*patches)[i];
-        if (p != NULL) {
-            free(p->data);
-            free(p);
-        }
-    }
-    free(*sha1s);
-    free(*patches);
-    return false;
 }
 
 static int FlashMode(const char* src_filename, const char* tgt_filename,
@@ -104,17 +90,17 @@
 }
 
 static int PatchMode(int argc, char** argv) {
-    Value* bonus = NULL;
+    std::unique_ptr<Value, decltype(&FreeValue)> bonus(nullptr, FreeValue);
     if (argc >= 3 && strcmp(argv[1], "-b") == 0) {
         FileContents fc;
         if (LoadFileContents(argv[2], &fc) != 0) {
             printf("failed to load bonus file %s\n", argv[2]);
             return 1;
         }
-        bonus = reinterpret_cast<Value*>(malloc(sizeof(Value)));
+        bonus.reset(new Value);
         bonus->type = VAL_BLOB;
         bonus->size = fc.size;
-        bonus->data = (char*)fc.data;
+        bonus->data = reinterpret_cast<char*>(fc.data);
         argc -= 2;
         argv += 2;
     }
@@ -140,33 +126,20 @@
     }
 
 
-    char** sha1s;
-    Value** patches;
-    int num_patches;
-    if (!ParsePatchArgs(argc-5, argv+5, &sha1s, &patches, &num_patches)) {
+    std::vector<char*> sha1s;
+    std::vector<std::unique_ptr<Value, decltype(&FreeValue)>> patches;
+    if (!ParsePatchArgs(argc-5, argv+5, &sha1s, &patches)) {
         printf("failed to parse patch args\n");
         return 1;
     }
 
-    int result = applypatch(argv[1], argv[2], argv[3], target_size,
-                            num_patches, sha1s, patches, bonus);
-
-    int i;
-    for (i = 0; i < num_patches; ++i) {
-        Value* p = patches[i];
-        if (p != NULL) {
-            free(p->data);
-            free(p);
-        }
+    std::vector<Value*> patch_ptrs;
+    for (const auto& p : patches) {
+        patch_ptrs.push_back(p.get());
     }
-    if (bonus) {
-        free(bonus->data);
-        free(bonus);
-    }
-    free(sha1s);
-    free(patches);
-
-    return result;
+    return applypatch(argv[1], argv[2], argv[3], target_size,
+                      patch_ptrs.size(), sha1s.data(),
+                      patch_ptrs.data(), bonus.get());
 }
 
 // This program applies binary patches to files in a way that is safe