df: Rework formatting, implement POSIX required flags

POSIX flags:
- -P for a fixed format usable in scripts with only some fields
- -k for kilobytes (the default for -P is 512 byte blocks). Rename -b to -k accordingly
  and implement a new -b to force 512 byte blocks

Default format rework:
- Add usage percentage
- To keep things under 80 columns, use two lines per device: the first
  shows the mountpoint and the second shows the details.
- Mount point is shown in bold and other fields are indented

Change-Id: I33843caf67ff01509ce38bf0b5fdd18517ea1aa9
Reviewed-on: https://review.haiku-os.org/c/haiku/+/9276
Tested-by: Commit checker robot <[email protected]>
Reviewed-by: Adrien Destugues <[email protected]>

src/bin/df.cpp

@@ -19,6 +19,15 @@
 #include <errno.h>
 
 
+enum FormatType
+{
+	k512Block,
+	k1024Block,
+	kHumanReadable,
+	kUnspecified
+};
+
+
 void
 PrintFlag(uint32 deviceFlags, uint32 testFlag, char yes, char no)
 {
@@ -58,7 +67,7 @@ PrintType(const char *fileSystem)
 	char type[16];
 	strlcpy(type, fileSystem, sizeof(type));
 
-	printf("%-9s", type);
+	printf("%11s ", type);
 }
 
 
@@ -87,13 +96,49 @@ ByteString(int64 numBlocks, int64 blockSize)
 }
 
 
+const char *
+UsePercentage(int64 totalBlocks, int64 freeBlocks, bool compact = false)
+{
+	float usage;
+	static char string[8];
+
+	if (totalBlocks == 0 && freeBlocks == 0)
+		usage = 100;
+	else if (totalBlocks == 0)
+		usage = 0;
+	else
+		usage = 100 - 100 * (1. * freeBlocks / totalBlocks);
+
+	if (compact) {
+		if (usage < 10)
+			sprintf(string, "  %.0f%%", round(usage));
+		else if (usage < 100)
+			sprintf(string, " %.0f%%", round(usage));
+		else
+			sprintf(string, "%.0f%%", round(usage));
+	}
+	else {
+		if (usage < 10)
+			sprintf(string, "  %.1f %%", usage);
+		else if (usage < 100)
+			sprintf(string, " %.1f %%", usage);
+		else
+			sprintf(string, "%.1f %%", usage);
+	}
+
+	return string;
+}
+
+
 void
-PrintBlocks(int64 blocks, int64 blockSize, bool showBlocks)
+PrintBlocks(int64 blocks, int64 blockSize, FormatType format)
 {
 	char temp[1024];
 
-	if (showBlocks)
+	if (format == k1024Block)
 		sprintf(temp, "%" B_PRId64, blocks * (blockSize / 1024));
+	else if (format == k512Block)
+		sprintf(temp, "%" B_PRId64, blocks * (blockSize / 512));
 	else
 		strcpy(temp, ByteString(blocks, blockSize));
 
@@ -110,6 +155,12 @@ PrintVerbose(dev_t device)
 		return;
 	}
 
+	int64 usedBlocks = info.total_blocks - info.free_blocks;
+	// Used blocks can't be negative, but ramfs reports available RAM as free_blocks,
+	// and always 0 for total_blocks, so we need to check for that.
+	if (usedBlocks < 0)
+		usedBlocks = 0;
+
 	printf("   Device No.: %" B_PRIdDEV "\n", info.dev);
 	PrintMountPoint(info.dev, true);
 	printf("  Volume Name: \"%s\"\n", info.volume_name);
@@ -131,16 +182,20 @@ PrintVerbose(dev_t device)
 		ByteString(info.block_size, 1), info.block_size);
 	printf(" Total Blocks: %10s (%" B_PRIdOFF " blocks)\n",
 		ByteString(info.total_blocks, info.block_size), info.total_blocks);
+	printf("  Used Blocks: %10s (%" B_PRIdOFF " blocks)\n",
+		ByteString(usedBlocks, info.block_size), usedBlocks);
 	printf("  Free Blocks: %10s (%" B_PRIdOFF " blocks)\n",
 		ByteString(info.free_blocks, info.block_size), info.free_blocks);
+	printf("      Usage %%:  %s\n", UsePercentage(info.total_blocks, info.free_blocks));
 	printf("  Total Nodes: %" B_PRIdOFF "\n", info.total_nodes);
+	printf("   Used Nodes: %" B_PRIdOFF "\n", info.total_nodes - info.free_nodes);
 	printf("   Free Nodes: %" B_PRIdOFF "\n", info.free_nodes);
 	printf("   Root Inode: %" B_PRIdINO "\n", info.root);
 }
 
 
 void
-PrintCompact(dev_t device, bool showBlocks, bool all)
+PrintCompact(dev_t device, FormatType format, bool strictPosix, bool all)
 {
 	fs_info info;
 	if (fs_stat_dev(device, &info) != B_OK)
@@ -149,21 +204,39 @@ PrintCompact(dev_t device, bool showBlocks, bool all)
 	if (!all && (info.flags & B_FS_IS_PERSISTENT) == 0)
 		return;
 
-	PrintType(info.fsh_name);
+	int64 usedBlocks = info.total_blocks - info.free_blocks;
-	PrintBlocks(info.total_blocks, info.block_size, showBlocks);
+	// Used blocks can't be negative, but ramfs reports available RAM as free_blocks,
-	PrintBlocks(info.free_blocks, info.block_size, showBlocks);
+	// and always 0 for total_blocks, so we need to check for that.
+	if (usedBlocks < 0)
+		usedBlocks = 0;
 
-	printf(" ");
+	if (strictPosix) {
-	PrintFlag(info.flags, B_FS_HAS_QUERY, 'Q', '-');
+		printf("%24s ", info.device_name);
-	PrintFlag(info.flags, B_FS_HAS_ATTR, 'A', '-');
+		PrintBlocks(info.total_blocks, info.block_size, format);
-	PrintFlag(info.flags, B_FS_HAS_MIME, 'M', '-');
+		PrintBlocks(usedBlocks, info.block_size, format);
-	PrintFlag(info.flags, B_FS_IS_SHARED, 'S', '-');
+		PrintBlocks(info.free_blocks, info.block_size, format);
-	PrintFlag(info.flags, B_FS_IS_PERSISTENT, 'P', '-');
+		printf("     %s ", UsePercentage(info.total_blocks, info.free_blocks, true));
-	PrintFlag(info.flags, B_FS_IS_REMOVABLE, 'R', '-');
+		PrintMountPoint(info.dev, false);
-	PrintFlag(info.flags, B_FS_IS_READONLY, '-', 'W');
+	} else {
+		printf("\x1B[1m");
+		PrintMountPoint(info.dev, false);
+		printf("\x1B[0m\n");
+		PrintType(info.fsh_name);
+		PrintBlocks(info.total_blocks, info.block_size, format);
+		PrintBlocks(usedBlocks, info.block_size, format);
 
-	printf(" %24s ", info.device_name);
+		printf(" ");
-	PrintMountPoint(info.dev, false);
+		PrintFlag(info.flags, B_FS_HAS_QUERY, 'Q', '-');
+		PrintFlag(info.flags, B_FS_HAS_ATTR, 'A', '-');
+		PrintFlag(info.flags, B_FS_HAS_MIME, 'M', '-');
+		PrintFlag(info.flags, B_FS_IS_SHARED, 'S', '-');
+		PrintFlag(info.flags, B_FS_IS_PERSISTENT, 'P', '-');
+		PrintFlag(info.flags, B_FS_IS_REMOVABLE, 'R', '-');
+		PrintFlag(info.flags, B_FS_IS_READONLY, '-', 'W');
+
+		printf(" %6s ", UsePercentage(info.total_blocks, info.free_blocks, true));
+		printf("%-24s", info.device_name);
+	}
 	printf("\n");
 }
 
@@ -171,10 +244,13 @@ PrintCompact(dev_t device, bool showBlocks, bool all)
 void
 ShowUsage(const char *programName)
 {
-	printf("usage: %s [--help | --blocks, -b | -all, -a] [<path-to-device>]\n"
+	printf("usage: %s [--help | --blocks, -b | -all, -a] [<path-to-volume>]\n"
 		"  -a, --all\tinclude all file systems, also those not visible from Tracker\n"
-		"  -b, --blocks\tshow device size in blocks of 1024 bytes\n"
+		"  -b, --blocks\tshow device size in blocks of 512 bytes\n"
-		"If <path-to-device> is used, detailed info for that device only will be listed.\n"
+		"  -h, --human\tshow device size in blocks of 1024 bytes\n"
+		"  -k, --kilobytes\tshow device size in blocks of 1024 bytes\n"
+		"  -P, --posix\tproduce output in the format specified by POSIX\n"
+		"If <path-to-volume> is used, detailed info for that volume only will be listed.\n"
 		"Flags:\n"
 		"   Q: has query\n"
 		"   A: has attribute\n"
@@ -194,7 +270,8 @@ main(int argc, char **argv)
 	if (strrchr(programName, '/'))
 		programName = strrchr(programName, '/') + 1;
 
-	bool showBlocks = false;
+	FormatType format = kUnspecified;
+	bool strictPosix = false;
 	bool all = false;
 	dev_t device = -1;
 
@@ -207,10 +284,17 @@ main(int argc, char **argv)
 						all = true;
 						break;
 					case 'b':
-						showBlocks = true;
+						format = k512Block;
 						break;
 					case 'h':
 						// human readable units in Unix df
+						format = kHumanReadable;
+						break;
+					case 'k':
+						format = k1024Block;
+						break;
+					case 'P':
+						strictPosix = true;
 						break;
 					default:
 						ShowUsage(programName);
@@ -221,7 +305,13 @@ main(int argc, char **argv)
 				if (!strcmp(arg, "all"))
 					all = true;
 				else if (!strcmp(arg, "blocks"))
-					showBlocks = true;
+					format = k512Block;
+				else if (!strcmp(arg, "human"))
+					format = kHumanReadable;
+				else if (!strcmp(arg, "kilobytes"))
+					format = k1024Block;
+				else if (!strcmp(arg, "posix"))
+					strictPosix = true;
 				else
 					ShowUsage(programName);
 			}
@@ -229,6 +319,17 @@ main(int argc, char **argv)
 			break;
 	}
 
+	// Determine default format if nothing was specified
+	// This is done after option parsing so that -k -P gives kilobytes as expected
+	// Otherwise -P could force 512-block format, but it would overwrite the effect of other
+	// options.
+	if (format == kUnspecified) {
+		if (strictPosix)
+			format = k512Block;
+		else
+			format = kHumanReadable;
+	}
+
 	// Do we already have a device? Then let's print out detailed info about that
 
 	if (argv[0] != NULL) {
@@ -238,12 +339,19 @@ main(int argc, char **argv)
 
 	// If not, then just iterate over all devices and give a compact summary
 
-	printf(" Type      Total     Free      Flags   Device                   Mounted on\n"
+	if (strictPosix) {
-		   "--------- --------- --------- ------- ------------------------ -----------------\n");
+		printf(" Filesystem             %11s Used      Available Capacity Mounted on\n",
+			format == kHumanReadable ? "Capacity"
+				: (format == k512Block ? "512-blocks" : "1024-blocks"));
+	} else {
+		printf("\x1B[1mVolume\x1B[0m\n"
+			   " Type        Total      Free      Flags   Used%% Device\n"
+			   "----------- ---------- --------- ------- ------ -------------------\n");
+	}
 
 	int32 cookie = 0;
 	while ((device = next_dev(&cookie)) >= B_OK) {
-		PrintCompact(device, showBlocks, all);
+		PrintCompact(device, format, strictPosix, all);
 	}
 
 	return 0;