Switch fastboot to new A/B spec
Slots are now referred to as a and b instead
of _a and _b. For the moment, _a and _b will
still be supported. For old devices that
support A/B, they are assumed to have 2 slots.
Bug: 29643845
Change-Id: Ieab6bed7b4977d8386dcec0afa434371f54bd63f
diff --git a/fastboot/fastboot.cpp b/fastboot/fastboot.cpp
index e5caae2..3b2999b 100644
--- a/fastboot/fastboot.cpp
+++ b/fastboot/fastboot.cpp
@@ -352,7 +352,7 @@
" override the fs type and/or size\n"
" the bootloader reports.\n"
" getvar <variable> Display a bootloader variable.\n"
- " set_active <suffix> Sets the active slot. If slots are\n"
+ " set_active <slot> Sets the active slot. If slots are\n"
" not supported, this does nothing.\n"
" boot <kernel> [ <ramdisk> [ <second> ] ] Download and boot kernel.\n"
" flash:raw boot <kernel> [ <ramdisk> [ <second> ] ]\n"
@@ -389,19 +389,21 @@
" (default: 2048).\n"
" -S <size>[K|M|G] Automatically sparse files greater\n"
" than 'size'. 0 to disable.\n"
- " --slot <suffix> Specify slot suffix to be used if the\n"
- " device supports slots. This will be\n"
- " added to all partition names that use\n"
- " slots. 'all' can be given to refer\n"
- " to all slots. 'other' can be given to\n"
- " refer to a non-current slot. If this\n"
- " flag is not used, slotted partitions\n"
- " will default to the current active slot.\n"
- " -a, --set-active[=<suffix>] Sets the active slot. If no suffix is\n"
+ " --slot <slot> Specify slot name to be used if the\n"
+ " device supports slots. All operations\n"
+ " on partitions that support slots will\n"
+ " be done on the slot specified.\n"
+ " 'all' can be given to refer to all slots.\n"
+ " 'other' can be given to refer to a\n"
+ " non-current slot. If this flag is not\n"
+ " used, slotted partitions will default\n"
+ " to the current active slot.\n"
+ " -a, --set-active[=<slot>] Sets the active slot. If no slot is\n"
" provided, this will default to the value\n"
" given by --slot. If slots are not\n"
- " supported, this does nothing. This will\n"
- " run after all non-reboot commands.\n"
+ " supported, this sets the current slot\n"
+ " to be active. This will run after all\n"
+ " non-reboot commands.\n"
#if !defined(_WIN32)
" --wipe-and-use-fbe On devices which support it,\n"
" erase userdata and cache, and\n"
@@ -862,7 +864,19 @@
}
}
-static std::vector<std::string> get_suffixes(Transport* transport) {
+static std::string get_current_slot(Transport* transport)
+{
+ std::string current_slot;
+ if (fb_getvar(transport, "current-slot", ¤t_slot)) {
+ if (current_slot == "_a") return "a"; // Legacy support
+ if (current_slot == "_b") return "b"; // Legacy support
+ return current_slot;
+ }
+ return "";
+}
+
+// Legacy support
+static std::vector<std::string> get_suffixes_obsolete(Transport* transport) {
std::vector<std::string> suffixes;
std::string suffix_list;
if (!fb_getvar(transport, "slot-suffixes", &suffix_list)) {
@@ -878,99 +892,110 @@
return suffixes;
}
+// Legacy support
+static bool supports_AB_obsolete(Transport* transport) {
+ return !get_suffixes_obsolete(transport).empty();
+}
+
+static int get_slot_count(Transport* transport) {
+ std::string var;
+ int count;
+ if (!fb_getvar(transport, "slot-count", &var)) {
+ if (supports_AB_obsolete(transport)) return 2; // Legacy support
+ }
+ if (!android::base::ParseInt(var.c_str(), &count)) return 0;
+ return count;
+}
+
static bool supports_AB(Transport* transport) {
- return !get_suffixes(transport).empty();
+ return get_slot_count(transport) >= 2;
}
// Given a current slot, this returns what the 'other' slot is.
-static std::string get_other_slot(Transport* transport, const std::string& current_slot) {
- std::vector<std::string> suffixes = get_suffixes(transport);
+static std::string get_other_slot(const std::string& current_slot, int count) {
+ if (count == 0) return "";
- if (!suffixes.empty()) {
- for (size_t i = 0; i < suffixes.size(); i++) {
- if (current_slot == suffixes[i]) {
- return suffixes[(i+1)%suffixes.size()];
- }
- }
- }
- return "";
+ char next = (current_slot[0] - 'a' + 1)%count + 'a';
+ return std::string(1, next);
+}
+
+static std::string get_other_slot(Transport* transport, const std::string& current_slot) {
+ return get_other_slot(current_slot, get_slot_count(transport));
+}
+
+static std::string get_other_slot(Transport* transport, int count) {
+ return get_other_slot(get_current_slot(transport), count);
}
static std::string get_other_slot(Transport* transport) {
- std::string current_slot;
- fb_getvar(transport, "current-slot", ¤t_slot);
- return get_other_slot(transport, current_slot);
+ return get_other_slot(get_current_slot(transport), get_slot_count(transport));
}
-static std::string verify_slot(Transport* transport, const char *slot, bool allow_all) {
- if (strcmp(slot, "all") == 0) {
+static std::string verify_slot(Transport* transport, const std::string& slot_name, bool allow_all) {
+ std::string slot = slot_name;
+ if (slot == "_a") slot = "a"; // Legacy support
+ if (slot == "_b") slot = "b"; // Legacy support
+ if (slot == "all") {
if (allow_all) {
return "all";
} else {
- std::vector<std::string> suffixes = get_suffixes(transport);
- if (!suffixes.empty()) {
- return suffixes[0];
+ int count = get_slot_count(transport);
+ if (count > 0) {
+ return "a";
} else {
die("No known slots.");
}
}
}
- std::vector<std::string> suffixes = get_suffixes(transport);
+ int count = get_slot_count(transport);
+ if (count == 0) die("Device does not support slots.\n");
- if (strcmp(slot, "other") == 0) {
- std::string current_slot;
- if (!fb_getvar(transport, "current-slot", ¤t_slot)) {
- die("Failed to identify current slot.");
- }
- std::string other = get_other_slot(transport, current_slot);
+ if (slot == "other") {
+ std::string other = get_other_slot(transport, count);
if (other == "") {
die("No known slots.");
}
return other;
}
- for (const std::string &suffix : suffixes) {
- if (suffix == slot)
- return slot;
+ if (slot.size() == 1 && (slot[0]-'a' >= 0 && slot[0]-'a' < count)) return slot;
+
+ fprintf(stderr, "Slot %s does not exist. supported slots are:\n", slot.c_str());
+ for (int i=0; i<count; i++) {
+ fprintf(stderr, "%c\n", (char)(i + 'a'));
}
- if (suffixes.empty()) {
- fprintf(stderr, "Device does not support slots.\n");
- } else {
- fprintf(stderr, "Slot %s does not exist. supported slots are:\n", slot);
- for (const std::string &suffix : suffixes) {
- fprintf(stderr, "%s\n", suffix.c_str());
- }
- }
+
exit(1);
}
-static std::string verify_slot(Transport* transport, const char *slot) {
+static std::string verify_slot(Transport* transport, const std::string& slot) {
return verify_slot(transport, slot, true);
}
-static void do_for_partition(Transport* transport, const char *part, const char *slot,
+static void do_for_partition(Transport* transport, const std::string& part, const std::string& slot,
std::function<void(const std::string&)> func, bool force_slot) {
std::string has_slot;
std::string current_slot;
- if (!fb_getvar(transport, std::string("has-slot:")+part, &has_slot)) {
+ if (!fb_getvar(transport, "has-slot:" + part, &has_slot)) {
/* If has-slot is not supported, the answer is no. */
has_slot = "no";
}
if (has_slot == "yes") {
- if (!slot || slot[0] == 0) {
- if (!fb_getvar(transport, "current-slot", ¤t_slot)) {
+ if (slot == "") {
+ current_slot = get_current_slot(transport);
+ if (current_slot == "") {
die("Failed to identify current slot.\n");
}
- func(std::string(part) + current_slot);
+ func(part + "_" + current_slot);
} else {
- func(std::string(part) + slot);
+ func(part + '_' + slot);
}
} else {
- if (force_slot && slot && slot[0]) {
+ if (force_slot && slot != "") {
fprintf(stderr, "Warning: %s does not support slots, and slot %s was requested.\n",
- part, slot);
+ part.c_str(), slot.c_str());
}
func(part);
}
@@ -981,21 +1006,17 @@
* partition names. If force_slot is true, it will fail if a slot is specified, and the given
* partition does not support slots.
*/
-static void do_for_partitions(Transport* transport, const char *part, const char *slot,
+static void do_for_partitions(Transport* transport, const std::string& part, const std::string& slot,
std::function<void(const std::string&)> func, bool force_slot) {
std::string has_slot;
- if (slot && strcmp(slot, "all") == 0) {
- if (!fb_getvar(transport, std::string("has-slot:") + part, &has_slot)) {
- die("Could not check if partition %s has slot.", part);
+ if (slot == "all") {
+ if (!fb_getvar(transport, "has-slot:" + part, &has_slot)) {
+ die("Could not check if partition %s has slot.", part.c_str());
}
if (has_slot == "yes") {
- std::vector<std::string> suffixes = get_suffixes(transport);
- if (suffixes.empty()) {
- die("Error reading suffixes.\n");
- }
- for (std::string &suffix : suffixes) {
- do_for_partition(transport, part, suffix.c_str(), func, force_slot);
+ for (int i=0; i < get_slot_count(transport); i++) {
+ do_for_partition(transport, part, std::string(1, (char)(i + 'a')), func, force_slot);
}
} else {
do_for_partition(transport, part, "", func, force_slot);
@@ -1025,15 +1046,20 @@
// Sets slot_override as the active slot. If slot_override is blank,
// set current slot as active instead. This clears slot-unbootable.
static void set_active(Transport* transport, const std::string& slot_override) {
+ std::string separator = "";
if (!supports_AB(transport)) {
- return;
- } else if (slot_override != "") {
- fb_set_active(slot_override.c_str());
+ if (supports_AB_obsolete(transport)) {
+ separator = "_"; // Legacy support
+ } else {
+ return;
+ }
+ }
+ if (slot_override != "") {
+ fb_set_active((separator + slot_override).c_str());
} else {
- std::string current_slot;
- if (fb_getvar(transport, "current-slot", ¤t_slot)) {
- current_slot = verify_slot(transport, current_slot.c_str(), false);
- fb_set_active(current_slot.c_str());
+ std::string current_slot = get_current_slot(transport);
+ if (current_slot != "") {
+ fb_set_active((separator + current_slot).c_str());
}
}
}
@@ -1510,20 +1536,23 @@
return 1;
}
- if (slot_override != "") slot_override = verify_slot(transport, slot_override.c_str());
- if (next_active != "") next_active = verify_slot(transport, next_active.c_str(), false);
+ if (!supports_AB(transport) && supports_AB_obsolete(transport)) {
+ fprintf(stderr, "Warning: Device A/B support is outdated. Bootloader update required.\n");
+ }
+ if (slot_override != "") slot_override = verify_slot(transport, slot_override);
+ if (next_active != "") next_active = verify_slot(transport, next_active, false);
if (wants_set_active) {
if (next_active == "") {
if (slot_override == "") {
std::string current_slot;
if (fb_getvar(transport, "current-slot", ¤t_slot)) {
- next_active = verify_slot(transport, current_slot.c_str(), false);
+ next_active = verify_slot(transport, current_slot, false);
} else {
wants_set_active = false;
}
} else {
- next_active = verify_slot(transport, slot_override.c_str(), false);
+ next_active = verify_slot(transport, slot_override, false);
}
}
}
@@ -1546,7 +1575,7 @@
fb_queue_erase(partition.c_str());
};
- do_for_partitions(transport, argv[1], slot_override.c_str(), erase, true);
+ do_for_partitions(transport, argv[1], slot_override, erase, true);
skip(2);
} else if(!strncmp(*argv, "format", strlen("format"))) {
char *overrides;
@@ -1582,7 +1611,7 @@
fb_perform_format(transport, partition.c_str(), 0,
type_override, size_override, "");
};
- do_for_partitions(transport, argv[1], slot_override.c_str(), format, true);
+ do_for_partitions(transport, argv[1], slot_override, format, true);
skip(2);
} else if(!strcmp(*argv, "signature")) {
require(2);
@@ -1649,7 +1678,7 @@
}
do_flash(transport, partition.c_str(), fname.c_str());
};
- do_for_partitions(transport, pname, slot_override.c_str(), flash, true);
+ do_for_partitions(transport, pname, slot_override, flash, true);
} else if(!strcmp(*argv, "flash:raw")) {
char *kname = argv[2];
char *rname = 0;
@@ -1669,7 +1698,7 @@
auto flashraw = [&](const std::string &partition) {
fb_queue_flash(partition.c_str(), data, sz);
};
- do_for_partitions(transport, argv[1], slot_override.c_str(), flashraw, true);
+ do_for_partitions(transport, argv[1], slot_override, flashraw, true);
} else if(!strcmp(*argv, "flashall")) {
skip(1);
if (slot_override == "all") {
@@ -1698,7 +1727,7 @@
wants_reboot = 1;
} else if(!strcmp(*argv, "set_active")) {
require(2);
- std::string slot = verify_slot(transport, argv[1], false);
+ std::string slot = verify_slot(transport, std::string(argv[1]), false);
fb_set_active(slot.c_str());
skip(2);
} else if(!strcmp(*argv, "oem")) {
