diff --git a/boot_control/boot_control_avb.c b/boot_control/boot_control_avb.c
index a4bdfe9..34bf13d 100644
--- a/boot_control/boot_control_avb.c
+++ b/boot_control/boot_control_avb.c
@@ -58,7 +58,7 @@
   } else if (strcmp(propbuf, "_b") == 0) {
     return 1;
   } else {
-    avb_errorv("Unexpected slot suffix '", propbuf, "'.\n", NULL);
+    avb_error("Unexpected slot suffix '", propbuf, "'.\n");
     return 0;
   }
   return 0;
diff --git a/examples/uefi/main.c b/examples/uefi/main.c
index 01dae48..887ac08 100644
--- a/examples/uefi/main.c
+++ b/examples/uefi/main.c
@@ -103,10 +103,9 @@
       }
       boot_result =
           uefi_avb_boot_kernel(ImageHandle, slot_data, additional_cmdline);
-      avb_fatalv("uefi_avb_boot_kernel() failed with error ",
-                 uefi_avb_boot_kernel_result_to_string(boot_result),
-                 "\n",
-                 NULL);
+      avb_fatal("uefi_avb_boot_kernel() failed with error ",
+                uefi_avb_boot_kernel_result_to_string(boot_result),
+                "\n");
       avb_slot_verify_data_free(slot_data);
       avb_free(additional_cmdline);
       break;
diff --git a/examples/uefi/uefi_avb_boot.c b/examples/uefi/uefi_avb_boot.c
index 800c9a1..d79d899 100644
--- a/examples/uefi/uefi_avb_boot.c
+++ b/examples/uefi/uefi_avb_boot.c
@@ -142,8 +142,7 @@
 
   boot = &slot_data->loaded_partitions[0];
   if (avb_strcmp(boot->partition_name, "boot") != 0) {
-    avb_errorv(
-        "Unexpected partition name '", boot->partition_name, "'.\n", NULL);
+    avb_error("Unexpected partition name '", boot->partition_name, "'.\n");
     ret = UEFI_AVB_BOOT_KERNEL_RESULT_ERROR_PARTITION_INVALID_FORMAT;
     goto out;
   }
diff --git a/libavb/avb_slot_verify.c b/libavb/avb_slot_verify.c
index a548c80..3f6007d 100644
--- a/libavb/avb_slot_verify.c
+++ b/libavb/avb_slot_verify.c
@@ -92,7 +92,7 @@
   /* We are going to implicitly cast image_size from uint64_t to size_t in the
    * following code, so we need to make sure that the cast is safe. */
   if (image_size != (size_t)(image_size)) {
-    avb_errorv(part_name, ": Partition size too large to load.\n", NULL);
+    avb_error(part_name, ": Partition size too large to load.\n");
     return AVB_SLOT_VERIFY_RESULT_ERROR_INVALID_METADATA;
   }
 
@@ -103,14 +103,14 @@
     if (io_ret == AVB_IO_RESULT_ERROR_OOM) {
       return AVB_SLOT_VERIFY_RESULT_ERROR_OOM;
     } else if (io_ret != AVB_IO_RESULT_OK) {
-      avb_errorv(part_name, ": Error loading data from partition.\n", NULL);
+      avb_error(part_name, ": Error loading data from partition.\n");
       return AVB_SLOT_VERIFY_RESULT_ERROR_IO;
     }
 
     if (*out_image_buf != NULL) {
       *out_image_preloaded = true;
       if (part_num_read != image_size) {
-        avb_errorv(part_name, ": Read incorrect number of bytes.\n", NULL);
+        avb_error(part_name, ": Read incorrect number of bytes.\n");
         return AVB_SLOT_VERIFY_RESULT_ERROR_IO;
       }
     }
@@ -132,11 +132,11 @@
     if (io_ret == AVB_IO_RESULT_ERROR_OOM) {
       return AVB_SLOT_VERIFY_RESULT_ERROR_OOM;
     } else if (io_ret != AVB_IO_RESULT_OK) {
-      avb_errorv(part_name, ": Error loading data from partition.\n", NULL);
+      avb_error(part_name, ": Error loading data from partition.\n");
       return AVB_SLOT_VERIFY_RESULT_ERROR_IO;
     }
     if (part_num_read != image_size) {
-      avb_errorv(part_name, ": Read incorrect number of bytes.\n", NULL);
+      avb_error(part_name, ": Read incorrect number of bytes.\n");
       return AVB_SLOT_VERIFY_RESULT_ERROR_IO;
     }
   }
@@ -170,7 +170,7 @@
   size_t stored_digest_size = 0;
 
   if (ops->read_persistent_value == NULL) {
-    avb_errorv(part_name, ": Persistent values are not implemented.\n", NULL);
+    avb_error(part_name, ": Persistent values are not implemented.\n");
     return AVB_SLOT_VERIFY_RESULT_ERROR_INVALID_METADATA;
   }
   persistent_value_name =
@@ -207,19 +207,17 @@
   } else if (io_ret == AVB_IO_RESULT_ERROR_NO_SUCH_VALUE) {
     // Treat a missing persistent value as a verification error, which is
     // ignoreable, rather than a metadata error which is not.
-    avb_errorv(part_name, ": Persistent digest does not exist.\n", NULL);
+    avb_error(part_name, ": Persistent digest does not exist.\n");
     return AVB_SLOT_VERIFY_RESULT_ERROR_VERIFICATION;
   } else if (io_ret == AVB_IO_RESULT_ERROR_INVALID_VALUE_SIZE ||
              io_ret == AVB_IO_RESULT_ERROR_INSUFFICIENT_SPACE) {
-    avb_errorv(
-        part_name, ": Persistent digest is not of expected size.\n", NULL);
+    avb_error(part_name, ": Persistent digest is not of expected size.\n");
     return AVB_SLOT_VERIFY_RESULT_ERROR_INVALID_METADATA;
   } else if (io_ret != AVB_IO_RESULT_OK) {
-    avb_errorv(part_name, ": Error reading persistent digest.\n", NULL);
+    avb_error(part_name, ": Error reading persistent digest.\n");
     return AVB_SLOT_VERIFY_RESULT_ERROR_IO;
   } else if (expected_digest_size != stored_digest_size) {
-    avb_errorv(
-        part_name, ": Persistent digest is not of expected size.\n", NULL);
+    avb_error(part_name, ": Persistent digest is not of expected size.\n");
     return AVB_SLOT_VERIFY_RESULT_ERROR_INVALID_METADATA;
   }
   return AVB_SLOT_VERIFY_RESULT_OK;
@@ -245,23 +243,21 @@
   }
 
   if (is_device_unlocked) {
-    avb_debugv(part_name,
-               ": Digest does not exist, device unlocked so not initializing "
-               "digest.\n",
-               NULL);
+    avb_debug(part_name,
+              ": Digest does not exist, device unlocked so not initializing "
+              "digest.\n");
     return AVB_SLOT_VERIFY_RESULT_ERROR_VERIFICATION;
   }
 
   // Device locked; initialize digest with given initial value.
-  avb_debugv(part_name,
-             ": Digest does not exist, initializing persistent digest.\n",
-             NULL);
+  avb_debug(part_name,
+            ": Digest does not exist, initializing persistent digest.\n");
   io_ret = ops->write_persistent_value(
       ops, persistent_value_name, digest_size, initial_digest);
   if (io_ret == AVB_IO_RESULT_ERROR_OOM) {
     return AVB_SLOT_VERIFY_RESULT_ERROR_OOM;
   } else if (io_ret != AVB_IO_RESULT_OK) {
-    avb_errorv(part_name, ": Error initializing persistent digest.\n", NULL);
+    avb_error(part_name, ": Error initializing persistent digest.\n");
     return AVB_SLOT_VERIFY_RESULT_ERROR_IO;
   }
 
@@ -271,9 +267,8 @@
   // initial_digest ensures that this will not recurse again.
   ret = read_persistent_digest(ops, part_name, digest_size, NULL, out_digest);
   if (ret != AVB_SLOT_VERIFY_RESULT_OK) {
-    avb_errorv(part_name,
-               ": Reading back initialized persistent digest failed!\n",
-               NULL);
+    avb_error(part_name,
+              ": Reading back initialized persistent digest failed!\n");
   }
   return ret;
 }
@@ -376,11 +371,11 @@
       ret = AVB_SLOT_VERIFY_RESULT_ERROR_OOM;
       goto out;
     } else if (io_ret != AVB_IO_RESULT_OK) {
-      avb_errorv(part_name, ": Error determining partition size.\n", NULL);
+      avb_error(part_name, ": Error determining partition size.\n");
       ret = AVB_SLOT_VERIFY_RESULT_ERROR_IO;
       goto out;
     }
-    avb_debugv(part_name, ": Loading entire partition.\n", NULL);
+    avb_debug(part_name, ": Loading entire partition.\n");
   }
 
   ret = load_full_partition(
@@ -412,14 +407,14 @@
     digest = avb_sha512_final(&sha512_ctx);
     digest_len = AVB_SHA512_DIGEST_SIZE;
   } else {
-    avb_errorv(part_name, ": Unsupported hash algorithm.\n", NULL);
+    avb_error(part_name, ": Unsupported hash algorithm.\n");
     ret = AVB_SLOT_VERIFY_RESULT_ERROR_INVALID_METADATA;
     goto out;
   }
 
   if (hash_desc.digest_len == 0) {
     /* Expect a match to a persistent digest. */
-    avb_debugv(part_name, ": No digest, using persistent digest.\n", NULL);
+    avb_debug(part_name, ": No digest, using persistent digest.\n");
     expected_digest_len = digest_len;
     expected_digest = expected_digest_buf;
     avb_assert(expected_digest_len <= sizeof(expected_digest_buf));
@@ -438,16 +433,14 @@
   }
 
   if (digest_len != expected_digest_len) {
-    avb_errorv(
-        part_name, ": Digest in descriptor not of expected size.\n", NULL);
+    avb_error(part_name, ": Digest in descriptor not of expected size.\n");
     ret = AVB_SLOT_VERIFY_RESULT_ERROR_INVALID_METADATA;
     goto out;
   }
 
   if (avb_safe_memcmp(digest, expected_digest, digest_len) != 0) {
-    avb_errorv(part_name,
-               ": Hash of data does not match digest in descriptor.\n",
-               NULL);
+    avb_error(part_name,
+              ": Hash of data does not match digest in descriptor.\n");
     ret = AVB_SLOT_VERIFY_RESULT_ERROR_VERIFICATION;
     goto out;
   }
@@ -461,7 +454,7 @@
       image_buf != NULL) {
     AvbPartitionData* loaded_partition;
     if (slot_data->num_loaded_partitions == MAX_NUMBER_OF_LOADED_PARTITIONS) {
-      avb_errorv(part_name, ": Too many loaded partitions.\n", NULL);
+      avb_error(part_name, ": Too many loaded partitions.\n");
       ret = AVB_SLOT_VERIFY_RESULT_ERROR_OOM;
       goto fail;
     }
@@ -514,11 +507,11 @@
       ret = AVB_SLOT_VERIFY_RESULT_ERROR_OOM;
       goto out;
     } else if (io_ret != AVB_IO_RESULT_OK) {
-      avb_errorv(part_name, ": Error determining partition size.\n", NULL);
+      avb_error(part_name, ": Error determining partition size.\n");
       ret = AVB_SLOT_VERIFY_RESULT_ERROR_IO;
       goto out;
     }
-    avb_debugv(part_name, ": Loading entire partition.\n", NULL);
+    avb_debug(part_name, ": Loading entire partition.\n");
 
     ret = load_full_partition(
         ops, part_name, image_size, &image_buf, &image_preloaded);
@@ -528,7 +521,7 @@
 
     /* Move to slot_data. */
     if (slot_data->num_loaded_partitions == MAX_NUMBER_OF_LOADED_PARTITIONS) {
-      avb_errorv(part_name, ": Too many loaded partitions.\n", NULL);
+      avb_error(part_name, ": Too many loaded partitions.\n");
       ret = AVB_SLOT_VERIFY_RESULT_ERROR_OOM;
       goto out;
     }
@@ -656,7 +649,7 @@
       ret = AVB_SLOT_VERIFY_RESULT_ERROR_OOM;
       goto out;
     } else if (io_ret != AVB_IO_RESULT_OK) {
-      avb_errorv(full_partition_name, ": Error loading footer.\n", NULL);
+      avb_error(full_partition_name, ": Error loading footer.\n");
       ret = AVB_SLOT_VERIFY_RESULT_ERROR_IO;
       goto out;
     }
@@ -664,12 +657,11 @@
 
     if (!avb_footer_validate_and_byteswap((const AvbFooter*)footer_buf,
                                           &footer)) {
-      avb_debugv(full_partition_name, ": No footer detected.\n", NULL);
+      avb_debug(full_partition_name, ": No footer detected.\n");
     } else {
       /* Basic footer sanity check since the data is untrusted. */
       if (footer.vbmeta_size > VBMETA_MAX_SIZE) {
-        avb_errorv(
-            full_partition_name, ": Invalid vbmeta size in footer.\n", NULL);
+        avb_error(full_partition_name, ": Invalid vbmeta size in footer.\n");
       } else {
         vbmeta_offset = footer.vbmeta_offset;
         vbmeta_size = footer.vbmeta_size;
@@ -681,13 +673,12 @@
         ops->get_size_of_partition(ops, full_partition_name, &partition_size);
     if (io_ret == AVB_IO_RESULT_OK) {
       if (partition_size < vbmeta_size && partition_size > 0) {
-        avb_debugv(full_partition_name,
-                   ": Using partition size as vbmeta size\n",
-                   NULL);
+        avb_debug(full_partition_name,
+                  ": Using partition size as vbmeta size\n");
         vbmeta_size = partition_size;
       }
     } else {
-      avb_debugv(full_partition_name, ": Failed to get partition size\n", NULL);
+      avb_debug(full_partition_name, ": Failed to get partition size\n");
       // libavb might fall back to other partitions if current vbmeta partition
       // isn't found. So AVB_IO_RESULT_ERROR_NO_SUCH_PARTITION is recoverable,
       // but other errors are not.
@@ -711,15 +702,13 @@
     }
 
     if (vbmeta_offset != 0) {
-      avb_debugv("Loading vbmeta struct in footer from partition '",
-                 full_partition_name,
-                 "'.\n",
-                 NULL);
+      avb_debug("Loading vbmeta struct in footer from partition '",
+                full_partition_name,
+                "'.\n");
     } else {
-      avb_debugv("Loading vbmeta struct from partition '",
-                 full_partition_name,
-                 "'.\n",
-                 NULL);
+      avb_debug("Loading vbmeta struct from partition '",
+                full_partition_name,
+                "'.\n");
     }
 
     io_ret = ops->read_from_partition(ops,
@@ -738,9 +727,8 @@
      */
     if (is_main_vbmeta && io_ret == AVB_IO_RESULT_ERROR_NO_SUCH_PARTITION &&
         !look_for_vbmeta_footer) {
-      avb_debugv(full_partition_name,
-                 ": No such partition. Trying 'boot' instead.\n",
-                 NULL);
+      avb_debug(full_partition_name,
+                ": No such partition. Trying 'boot' instead.\n");
       ret = load_and_verify_vbmeta(ops,
                                    requested_partitions,
                                    ab_suffix,
@@ -757,7 +745,7 @@
                                    out_additional_cmdline_subst);
       goto out;
     } else {
-      avb_errorv(full_partition_name, ": Error loading vbmeta data.\n", NULL);
+      avb_error(full_partition_name, ": Error loading vbmeta data.\n");
       ret = AVB_SLOT_VERIFY_RESULT_ERROR_IO;
       goto out;
     }
@@ -778,11 +766,10 @@
     case AVB_VBMETA_VERIFY_RESULT_HASH_MISMATCH:
     case AVB_VBMETA_VERIFY_RESULT_SIGNATURE_MISMATCH:
       ret = AVB_SLOT_VERIFY_RESULT_ERROR_VERIFICATION;
-      avb_errorv(full_partition_name,
-                 ": Error verifying vbmeta image: ",
-                 avb_vbmeta_verify_result_to_string(vbmeta_ret),
-                 "\n",
-                 NULL);
+      avb_error(full_partition_name,
+                ": Error verifying vbmeta image: ",
+                avb_vbmeta_verify_result_to_string(vbmeta_ret),
+                "\n");
       if (!allow_verification_error) {
         goto out;
       }
@@ -791,17 +778,15 @@
     case AVB_VBMETA_VERIFY_RESULT_INVALID_VBMETA_HEADER:
       /* No way to continue this case. */
       ret = AVB_SLOT_VERIFY_RESULT_ERROR_INVALID_METADATA;
-      avb_errorv(full_partition_name,
-                 ": Error verifying vbmeta image: invalid vbmeta header\n",
-                 NULL);
+      avb_error(full_partition_name,
+                ": Error verifying vbmeta image: invalid vbmeta header\n");
       goto out;
 
     case AVB_VBMETA_VERIFY_RESULT_UNSUPPORTED_VERSION:
       /* No way to continue this case. */
       ret = AVB_SLOT_VERIFY_RESULT_ERROR_UNSUPPORTED_VERSION;
-      avb_errorv(full_partition_name,
-                 ": Error verifying vbmeta image: unsupported AVB version\n",
-                 NULL);
+      avb_error(full_partition_name,
+                ": Error verifying vbmeta image: unsupported AVB version\n");
       goto out;
   }
 
@@ -815,9 +800,8 @@
   } else {
     if (vbmeta_header.flags != 0) {
       ret = AVB_SLOT_VERIFY_RESULT_ERROR_INVALID_METADATA;
-      avb_errorv(full_partition_name,
-                 ": chained vbmeta image has non-zero flags\n",
-                 NULL);
+      avb_error(full_partition_name,
+                ": chained vbmeta image has non-zero flags\n");
       goto out;
     }
   }
@@ -833,10 +817,9 @@
       avb_assert(!is_main_vbmeta);
       if (expected_public_key_length != pk_len ||
           avb_safe_memcmp(expected_public_key, pk_data, pk_len) != 0) {
-        avb_errorv(full_partition_name,
-                   ": Public key used to sign data does not match key in chain "
-                   "partition descriptor.\n",
-                   NULL);
+        avb_error(full_partition_name,
+                  ": Public key used to sign data does not match key in chain "
+                  "partition descriptor.\n");
         ret = AVB_SLOT_VERIFY_RESULT_ERROR_PUBLIC_KEY_REJECTED;
         if (!allow_verification_error) {
           goto out;
@@ -879,16 +862,14 @@
         ret = AVB_SLOT_VERIFY_RESULT_ERROR_OOM;
         goto out;
       } else if (io_ret != AVB_IO_RESULT_OK) {
-        avb_errorv(full_partition_name,
-                   ": Error while checking public key used to sign data.\n",
-                   NULL);
+        avb_error(full_partition_name,
+                  ": Error while checking public key used to sign data.\n");
         ret = AVB_SLOT_VERIFY_RESULT_ERROR_IO;
         goto out;
       }
       if (!key_is_trusted) {
-        avb_errorv(full_partition_name,
-                   ": Public key used to sign data rejected.\n",
-                   NULL);
+        avb_error(full_partition_name,
+                  ": Public key used to sign data rejected.\n");
         ret = AVB_SLOT_VERIFY_RESULT_ERROR_PUBLIC_KEY_REJECTED;
         if (!allow_verification_error) {
           goto out;
@@ -904,17 +885,15 @@
     ret = AVB_SLOT_VERIFY_RESULT_ERROR_OOM;
     goto out;
   } else if (io_ret != AVB_IO_RESULT_OK) {
-    avb_errorv(full_partition_name,
-               ": Error getting rollback index for location.\n",
-               NULL);
+    avb_error(full_partition_name,
+              ": Error getting rollback index for location.\n");
     ret = AVB_SLOT_VERIFY_RESULT_ERROR_IO;
     goto out;
   }
   if (vbmeta_header.rollback_index < stored_rollback_index) {
-    avb_errorv(
+    avb_error(
         full_partition_name,
-        ": Image rollback index is less than the stored rollback index.\n",
-        NULL);
+        ": Image rollback index is less than the stored rollback index.\n");
     ret = AVB_SLOT_VERIFY_RESULT_ERROR_ROLLBACK_INDEX;
     if (!allow_verification_error) {
       goto out;
@@ -930,7 +909,7 @@
     }
   }
   if (slot_data->num_vbmeta_images == MAX_NUMBER_OF_VBMETA_IMAGES) {
-    avb_errorv(full_partition_name, ": Too many vbmeta images.\n", NULL);
+    avb_error(full_partition_name, ": Too many vbmeta images.\n");
     ret = AVB_SLOT_VERIFY_RESULT_ERROR_OOM;
     goto out;
   }
@@ -954,8 +933,7 @@
    */
   if (vbmeta_header.flags & AVB_VBMETA_IMAGE_FLAGS_VERIFICATION_DISABLED) {
     AvbSlotVerifyResult sub_ret;
-    avb_debugv(
-        full_partition_name, ": VERIFICATION_DISABLED bit is set.\n", NULL);
+    avb_debug(full_partition_name, ": VERIFICATION_DISABLED bit is set.\n");
     /* If load_requested_partitions() fail it is always a fatal
      * failure (e.g. ERROR_INVALID_ARGUMENT, ERROR_OOM, etc.) rather
      * than recoverable (e.g. one where result_should_continue()
@@ -988,7 +966,7 @@
     AvbDescriptor desc;
 
     if (!avb_descriptor_validate_and_byteswap(descriptors[n], &desc)) {
-      avb_errorv(full_partition_name, ": Descriptor is invalid.\n", NULL);
+      avb_error(full_partition_name, ": Descriptor is invalid.\n");
       ret = AVB_SLOT_VERIFY_RESULT_ERROR_INVALID_METADATA;
       goto out;
     }
@@ -1018,27 +996,24 @@
 
         /* Only allow CHAIN_PARTITION descriptors in the main vbmeta image. */
         if (!is_main_vbmeta) {
-          avb_errorv(full_partition_name,
-                     ": Encountered chain descriptor not in main image.\n",
-                     NULL);
+          avb_error(full_partition_name,
+                    ": Encountered chain descriptor not in main image.\n");
           ret = AVB_SLOT_VERIFY_RESULT_ERROR_INVALID_METADATA;
           goto out;
         }
 
         if (!avb_chain_partition_descriptor_validate_and_byteswap(
                 (AvbChainPartitionDescriptor*)descriptors[n], &chain_desc)) {
-          avb_errorv(full_partition_name,
-                     ": Chain partition descriptor is invalid.\n",
-                     NULL);
+          avb_error(full_partition_name,
+                    ": Chain partition descriptor is invalid.\n");
           ret = AVB_SLOT_VERIFY_RESULT_ERROR_INVALID_METADATA;
           goto out;
         }
 
         if (chain_desc.rollback_index_location == 0) {
-          avb_errorv(full_partition_name,
-                     ": Chain partition has invalid "
-                     "rollback_index_location field.\n",
-                     NULL);
+          avb_error(full_partition_name,
+                    ": Chain partition has invalid "
+                    "rollback_index_location field.\n");
           ret = AVB_SLOT_VERIFY_RESULT_ERROR_INVALID_METADATA;
           goto out;
         }
@@ -1078,9 +1053,8 @@
         if (!avb_kernel_cmdline_descriptor_validate_and_byteswap(
                 (AvbKernelCmdlineDescriptor*)descriptors[n],
                 &kernel_cmdline_desc)) {
-          avb_errorv(full_partition_name,
-                     ": Kernel cmdline descriptor is invalid.\n",
-                     NULL);
+          avb_error(full_partition_name,
+                    ": Kernel cmdline descriptor is invalid.\n");
           ret = AVB_SLOT_VERIFY_RESULT_ERROR_INVALID_METADATA;
           goto out;
         }
@@ -1090,9 +1064,8 @@
 
         if (!avb_validate_utf8(kernel_cmdline,
                                kernel_cmdline_desc.kernel_cmdline_length)) {
-          avb_errorv(full_partition_name,
-                     ": Kernel cmdline is not valid UTF-8.\n",
-                     NULL);
+          avb_error(full_partition_name,
+                    ": Kernel cmdline is not valid UTF-8.\n");
           ret = AVB_SLOT_VERIFY_RESULT_ERROR_INVALID_METADATA;
           goto out;
         }
@@ -1152,8 +1125,7 @@
 
         if (!avb_hashtree_descriptor_validate_and_byteswap(
                 (AvbHashtreeDescriptor*)descriptors[n], &hashtree_desc)) {
-          avb_errorv(
-              full_partition_name, ": Hashtree descriptor is invalid.\n", NULL);
+          avb_error(full_partition_name, ": Hashtree descriptor is invalid.\n");
           ret = AVB_SLOT_VERIFY_RESULT_ERROR_INVALID_METADATA;
           goto out;
         }
@@ -1207,7 +1179,7 @@
                                 "sha512") == 0) {
             digest_len = AVB_SHA512_DIGEST_SIZE;
           } else {
-            avb_errorv(part_name, ": Unsupported hash algorithm.\n", NULL);
+            avb_error(part_name, ": Unsupported hash algorithm.\n");
             ret = AVB_SLOT_VERIFY_RESULT_ERROR_INVALID_METADATA;
             goto out;
           }
@@ -1242,8 +1214,7 @@
 
   if (rollback_index_location_to_use >=
       AVB_MAX_NUMBER_OF_ROLLBACK_INDEX_LOCATIONS) {
-    avb_errorv(
-        full_partition_name, ": Invalid rollback_index_location.\n", NULL);
+    avb_error(full_partition_name, ": Invalid rollback_index_location.\n");
     ret = AVB_SLOT_VERIFY_RESULT_ERROR_INVALID_METADATA;
     goto out;
   }
diff --git a/libavb/avb_sysdeps.h b/libavb/avb_sysdeps.h
index e511a8a..b4a1e99 100644
--- a/libavb/avb_sysdeps.h
+++ b/libavb/avb_sysdeps.h
@@ -48,6 +48,7 @@
  */
 #define AVB_ATTR_WARN_UNUSED_RESULT __attribute__((warn_unused_result))
 #define AVB_ATTR_PACKED __attribute__((packed))
+#define AVB_ATTR_PRINTF(x, y) __attribute__((format(printf, x, y)))
 #define AVB_ATTR_NO_RETURN __attribute__((noreturn))
 #define AVB_ATTR_SENTINEL __attribute__((__sentinel__))
 
@@ -95,10 +96,16 @@
 void avb_print(const char* message);
 
 /* Prints out a vector of strings. Each argument must point to a
- * NUL-terminated UTF-8 string and NULL should be the last argument.
+ * NUL-terminated UTF-8 string and NULL must be the last argument.
  */
 void avb_printv(const char* message, ...) AVB_ATTR_SENTINEL;
 
+/* Prints out a formatted string.
+ *
+ * Replaces avb_printv when AVB_USE_PRINTF_LOGS is enabled.
+ */
+void avb_printf(const char* fmt, ...) AVB_ATTR_PRINTF(1, 2);
+
 /* Aborts the program or reboots the device. */
 void avb_abort(void) AVB_ATTR_NO_RETURN;
 
diff --git a/libavb/avb_sysdeps_posix.c b/libavb/avb_sysdeps_posix.c
index e26c3ef..a954869 100644
--- a/libavb/avb_sysdeps_posix.c
+++ b/libavb/avb_sysdeps_posix.c
@@ -58,6 +58,13 @@
   abort();
 }
 
+void avb_printf(const char* fmt, ...) {
+  va_list ap;
+  va_start(ap, fmt);
+  vfprintf(stderr, fmt, ap);
+  va_end(ap);
+}
+
 void avb_print(const char* message) {
   fprintf(stderr, "%s", message);
 }
diff --git a/libavb/avb_util.h b/libavb/avb_util.h
index b6b036e..da638fc 100644
--- a/libavb/avb_util.h
+++ b/libavb/avb_util.h
@@ -35,9 +35,44 @@
 extern "C" {
 #endif
 
+#define AVB_CONCAT(x, y) x##y
 #define AVB_STRINGIFY(x) #x
 #define AVB_TO_STRING(x) AVB_STRINGIFY(x)
 
+#define AVB__COUNT_ARGS(_0, _1, _2, _3, _4, _5, _6, _7, x, ...) x
+#define AVB_COUNT_ARGS(...) \
+  AVB__COUNT_ARGS(, ##__VA_ARGS__, 7, 6, 5, 4, 3, 2, 1, 0)
+
+#define AVB__REPEAT0(x)
+#define AVB__REPEAT1(x) x
+#define AVB__REPEAT2(x) AVB__REPEAT1(x) x
+#define AVB__REPEAT3(x) AVB__REPEAT2(x) x
+#define AVB__REPEAT4(x) AVB__REPEAT3(x) x
+#define AVB__REPEAT5(x) AVB__REPEAT4(x) x
+#define AVB__REPEAT6(x) AVB__REPEAT5(x) x
+#define AVB__REPEAT7(x) AVB__REPEAT6(x) x
+#define AVB__REPEAT(n, x) AVB_CONCAT(AVB__REPEAT, n)(x)
+#define AVB_REPEAT(n, x) AVB__REPEAT(n, x)
+
+#ifdef AVB_USE_PRINTF_LOGS
+#define AVB_LOG(level, message, ...)                                        \
+  avb_printf("%s:%d: " level                                                \
+             ": " AVB_REPEAT(AVB_COUNT_ARGS(message, ##__VA_ARGS__), "%s"), \
+             avb_basename(__FILE__),                                        \
+             __LINE__,                                                      \
+             message,                                                       \
+             ##__VA_ARGS__)
+#else
+#define AVB_LOG(level, message, ...)  \
+  avb_printv(avb_basename(__FILE__),  \
+             ":",                     \
+             AVB_TO_STRING(__LINE__), \
+             ": " level ": ",         \
+             message,                 \
+             ##__VA_ARGS__,           \
+             NULL)
+#endif
+
 #ifdef AVB_ENABLE_DEBUG
 /* Aborts the program if |expr| is false.
  *
@@ -49,21 +84,28 @@
       avb_fatal("assert fail: " #expr "\n"); \
     }                                        \
   } while (0)
-#else
-#define avb_assert(expr)
-#endif
 
 /* Aborts the program if reached.
  *
  * This has no effect unless AVB_ENABLE_DEBUG is defined.
  */
-#ifdef AVB_ENABLE_DEBUG
 #define avb_assert_not_reached()         \
   do {                                   \
     avb_fatal("assert_not_reached()\n"); \
   } while (0)
+
+/* Print functions, used for diagnostics.
+ *
+ * These have no effect unless AVB_ENABLE_DEBUG is defined.
+ */
+#define avb_debug(message, ...)               \
+  do {                                        \
+    AVB_LOG("DEBUG", message, ##__VA_ARGS__); \
+  } while (0)
 #else
+#define avb_assert(expr)
 #define avb_assert_not_reached()
+#define avb_debug(message, ...)
 #endif
 
 /* Aborts the program if |addr| is not word-aligned.
@@ -73,78 +115,29 @@
 #define avb_assert_aligned(addr) \
   avb_assert((((uintptr_t)addr) & (AVB_ALIGNMENT_SIZE - 1)) == 0)
 
-#ifdef AVB_ENABLE_DEBUG
-/* Print functions, used for diagnostics.
- *
- * These have no effect unless AVB_ENABLE_DEBUG is defined.
- */
-#define avb_debug(message)              \
-  do {                                  \
-    avb_printv(avb_basename(__FILE__),  \
-               ":",                     \
-               AVB_TO_STRING(__LINE__), \
-               ": DEBUG: ",             \
-               message,                 \
-               NULL);                   \
-  } while (0)
-#define avb_debugv(message, ...)        \
-  do {                                  \
-    avb_printv(avb_basename(__FILE__),  \
-               ":",                     \
-               AVB_TO_STRING(__LINE__), \
-               ": DEBUG: ",             \
-               message,                 \
-               ##__VA_ARGS__);          \
-  } while (0)
-#else
-#define avb_debug(message)
-#define avb_debugv(message, ...)
-#endif
-
 /* Prints out a message. This is typically used if a runtime-error
  * occurs.
  */
-#define avb_error(message)              \
-  do {                                  \
-    avb_printv(avb_basename(__FILE__),  \
-               ":",                     \
-               AVB_TO_STRING(__LINE__), \
-               ": ERROR: ",             \
-               message,                 \
-               NULL);                   \
-  } while (0)
-#define avb_errorv(message, ...)        \
-  do {                                  \
-    avb_printv(avb_basename(__FILE__),  \
-               ":",                     \
-               AVB_TO_STRING(__LINE__), \
-               ": ERROR: ",             \
-               message,                 \
-               ##__VA_ARGS__);          \
+#define avb_error(message, ...)               \
+  do {                                        \
+    AVB_LOG("ERROR", message, ##__VA_ARGS__); \
   } while (0)
 
 /* Prints out a message and calls avb_abort().
  */
-#define avb_fatal(message)              \
-  do {                                  \
-    avb_printv(avb_basename(__FILE__),  \
-               ":",                     \
-               AVB_TO_STRING(__LINE__), \
-               ": FATAL: ",             \
-               message,                 \
-               NULL);                   \
-    avb_abort();                        \
+#define avb_fatal(message, ...)               \
+  do {                                        \
+    AVB_LOG("FATAL", message, ##__VA_ARGS__); \
+    avb_abort();                              \
   } while (0)
-#define avb_fatalv(message, ...)        \
-  do {                                  \
-    avb_printv(avb_basename(__FILE__),  \
-               ":",                     \
-               AVB_TO_STRING(__LINE__), \
-               ": FATAL: ",             \
-               message,                 \
-               ##__VA_ARGS__);          \
-    avb_abort();                        \
-  } while (0)
+
+#ifndef AVB_USE_PRINTF_LOGS
+/* Deprecated legacy logging functions -- kept for client compatibility.
+ */
+#define avb_debugv(message, ...) avb_debug(message, ##__VA_ARGS__)
+#define avb_errorv(message, ...) avb_error(message, ##__VA_ARGS__)
+#define avb_fatalv(message, ...) avb_fatal(message, ##__VA_ARGS__)
+#endif
 
 /* Converts a 16-bit unsigned integer from big-endian to host byte order. */
 uint16_t avb_be16toh(uint16_t in) AVB_ATTR_WARN_UNUSED_RESULT;
diff --git a/libavb_ab/avb_ab_flow.c b/libavb_ab/avb_ab_flow.c
index bf6eab1..cbdf6c9 100644
--- a/libavb_ab/avb_ab_flow.c
+++ b/libavb_ab/avb_ab_flow.c
@@ -263,15 +263,12 @@
         case AVB_SLOT_VERIFY_RESULT_ERROR_PUBLIC_KEY_REJECTED:
           if (flags & AVB_SLOT_VERIFY_FLAGS_ALLOW_VERIFICATION_ERROR) {
             /* Do nothing since we allow this. */
-            avb_debugv("Allowing slot ",
-                       slot_suffixes[n],
-                       " which verified "
-                       "with result ",
-                       avb_slot_verify_result_to_string(verify_result),
-                       " because "
-                       "AVB_SLOT_VERIFY_FLAGS_ALLOW_VERIFICATION_ERROR "
-                       "is set.\n",
-                       NULL);
+            avb_debug("Allowing slot ",
+                      slot_suffixes[n],
+                      " which verified with result ",
+                      avb_slot_verify_result_to_string(verify_result),
+                      " because AVB_SLOT_VERIFY_FLAGS_ALLOW_VERIFICATION_ERROR "
+                      "is set.\n");
             saw_and_allowed_verification_error = true;
           } else {
             set_slot_unbootable = true;
@@ -285,12 +282,11 @@
       }
 
       if (set_slot_unbootable) {
-        avb_errorv("Error verifying slot ",
-                   slot_suffixes[n],
-                   " with result ",
-                   avb_slot_verify_result_to_string(verify_result),
-                   " - setting unbootable.\n",
-                   NULL);
+        avb_error("Error verifying slot ",
+                  slot_suffixes[n],
+                  " with result ",
+                  avb_slot_verify_result_to_string(verify_result),
+                  " - setting unbootable.\n");
         slot_set_unbootable(&ab_data.slots[n]);
       }
     }
diff --git a/libavb_user/avb_ops_user.cpp b/libavb_user/avb_ops_user.cpp
index d7815f0..1ce5391 100644
--- a/libavb_user/avb_ops_user.cpp
+++ b/libavb_user/avb_ops_user.cpp
@@ -138,8 +138,7 @@
   if (offset < 0) {
     uint64_t partition_size;
     if (ioctl(fd, BLKGETSIZE64, &partition_size) != 0) {
-      avb_errorv(
-          "Error getting size of \"", partition, "\" partition.\n", NULL);
+      avb_error("Error getting size of \"", partition, "\" partition.\n");
       ret = AVB_IO_RESULT_ERROR_IO;
       goto out;
     }
@@ -194,7 +193,7 @@
 
   fd = open_partition(partition, O_WRONLY);
   if (fd == -1) {
-    avb_errorv("Error opening \"", partition, "\" partition.\n", NULL);
+    avb_error("Error opening \"", partition, "\" partition.\n");
     ret = AVB_IO_RESULT_ERROR_IO;
     goto out;
   }
@@ -273,15 +272,14 @@
 
   fd = open_partition(partition, O_WRONLY);
   if (fd == -1) {
-    avb_errorv("Error opening \"", partition, "\" partition.\n", NULL);
+    avb_error("Error opening \"", partition, "\" partition.\n");
     ret = AVB_IO_RESULT_ERROR_IO;
     goto out;
   }
 
   if (out_size_in_bytes != NULL) {
     if (ioctl(fd, BLKGETSIZE64, out_size_in_bytes) != 0) {
-      avb_errorv(
-          "Error getting size of \"", partition, "\" partition.\n", NULL);
+      avb_error("Error getting size of \"", partition, "\" partition.\n");
       ret = AVB_IO_RESULT_ERROR_IO;
       goto out;
     }
diff --git a/libavb_user/avb_user_verification.c b/libavb_user/avb_user_verification.c
index f572128..7a124d8 100644
--- a/libavb_user/avb_user_verification.c
+++ b/libavb_user/avb_user_verification.c
@@ -86,18 +86,15 @@
                                       &footer,
                                       &num_read);
     if (io_res != AVB_IO_RESULT_OK) {
-      avb_errorv("Error loading footer from partition '",
-                 out_partition_name,
-                 "'\n",
-                 NULL);
+      avb_error(
+          "Error loading footer from partition '", out_partition_name, "'\n");
       goto out;
     }
 
     if (avb_memcmp(footer.magic, AVB_FOOTER_MAGIC, AVB_FOOTER_MAGIC_LEN) != 0) {
-      avb_errorv("Data from '",
-                 out_partition_name,
-                 "' does not look like a vbmeta footer.\n",
-                 NULL);
+      avb_error("Data from '",
+                out_partition_name,
+                "' does not look like a vbmeta footer.\n");
       goto out;
     }
 
@@ -111,8 +108,7 @@
   }
 
   if (io_res != AVB_IO_RESULT_OK) {
-    avb_errorv(
-        "Error loading from partition '", out_partition_name, "'\n", NULL);
+    avb_error("Error loading from partition '", out_partition_name, "'\n");
     goto out;
   }
 
@@ -141,10 +137,9 @@
   }
 
   if (avb_memcmp(vbmeta_image, AVB_MAGIC, AVB_MAGIC_LEN) != 0) {
-    avb_errorv("Data from '",
-               partition_name,
-               "' does not look like a vbmeta header.\n",
-               NULL);
+    avb_error("Data from '",
+              partition_name,
+              "' does not look like a vbmeta header.\n");
     goto out;
   }
 
@@ -180,10 +175,9 @@
   }
 
   if (avb_memcmp(vbmeta_image, AVB_MAGIC, AVB_MAGIC_LEN) != 0) {
-    avb_errorv("Data from '",
-               partition_name,
-               "' does not look like a vbmeta header.\n",
-               NULL);
+    avb_error("Data from '",
+              partition_name,
+              "' does not look like a vbmeta header.\n");
     goto out;
   }
 
@@ -203,7 +197,7 @@
                                    AVB_VBMETA_IMAGE_HEADER_SIZE,
                                    vbmeta_image);
   if (io_res != AVB_IO_RESULT_OK) {
-    avb_errorv("Error writing to partition '", partition_name, "'\n", NULL);
+    avb_error("Error writing to partition '", partition_name, "'\n");
     goto out;
   }
 
diff --git a/libavb_user/avb_user_verity.c b/libavb_user/avb_user_verity.c
index ecf0043..dd64b3c 100644
--- a/libavb_user/avb_user_verity.c
+++ b/libavb_user/avb_user_verity.c
@@ -86,18 +86,15 @@
                                       &footer,
                                       &num_read);
     if (io_res != AVB_IO_RESULT_OK) {
-      avb_errorv("Error loading footer from partition '",
-                 out_partition_name,
-                 "'\n",
-                 NULL);
+      avb_error(
+          "Error loading footer from partition '", out_partition_name, "'\n");
       goto out;
     }
 
     if (avb_memcmp(footer.magic, AVB_FOOTER_MAGIC, AVB_FOOTER_MAGIC_LEN) != 0) {
-      avb_errorv("Data from '",
-                 out_partition_name,
-                 "' does not look like a vbmeta footer.\n",
-                 NULL);
+      avb_error("Data from '",
+                out_partition_name,
+                "' does not look like a vbmeta footer.\n");
       goto out;
     }
 
@@ -111,8 +108,7 @@
   }
 
   if (io_res != AVB_IO_RESULT_OK) {
-    avb_errorv(
-        "Error loading from partition '", out_partition_name, "'\n", NULL);
+    avb_error("Error loading from partition '", out_partition_name, "'\n");
     goto out;
   }
 
@@ -141,10 +137,9 @@
   }
 
   if (avb_memcmp(vbmeta_image, AVB_MAGIC, AVB_MAGIC_LEN) != 0) {
-    avb_errorv("Data from '",
-               partition_name,
-               "' does not look like a vbmeta header.\n",
-               NULL);
+    avb_error("Data from '",
+              partition_name,
+              "' does not look like a vbmeta header.\n");
     goto out;
   }
 
@@ -179,10 +174,9 @@
   }
 
   if (avb_memcmp(vbmeta_image, AVB_MAGIC, AVB_MAGIC_LEN) != 0) {
-    avb_errorv("Data from '",
-               partition_name,
-               "' does not look like a vbmeta header.\n",
-               NULL);
+    avb_error("Data from '",
+              partition_name,
+              "' does not look like a vbmeta header.\n");
     goto out;
   }
 
@@ -202,7 +196,7 @@
                                    AVB_VBMETA_IMAGE_HEADER_SIZE,
                                    vbmeta_image);
   if (io_res != AVB_IO_RESULT_OK) {
-    avb_errorv("Error writing to partition '", partition_name, "'\n", NULL);
+    avb_error("Error writing to partition '", partition_name, "'\n");
     goto out;
   }
 
diff --git a/test/avb_sysdeps_posix_testing.cc b/test/avb_sysdeps_posix_testing.cc
index 0a6ac13..6b1f210 100644
--- a/test/avb_sysdeps_posix_testing.cc
+++ b/test/avb_sysdeps_posix_testing.cc
@@ -77,6 +77,13 @@
   va_end(ap);
 }
 
+void avb_printf(const char* fmt, ...) {
+  va_list ap;
+  va_start(ap, fmt);
+  vfprintf(stderr, fmt, ap);
+  va_end(ap);
+}
+
 typedef struct {
   size_t size;
   base::debug::StackTrace stack_trace;