Update documentation generator so that it sucks less

Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>

4 files changed, 121 insertions, 20 deletions

diff --git a/applets/Kbuild b/applets/Kbuild
index 983037987..a966f6e5b 100644
--- a/applets/Kbuild
+++ b/applets/Kbuild
@@ -8,7 +8,7 @@ obj-y :=
 obj-y += applets.o
 
 hostprogs-y:=
-hostprogs-y += usage applet_tables
+hostprogs-y += usage usage_pod applet_tables
 
 always:= $(hostprogs-y)
 
@@ -22,13 +22,14 @@ else
 srctree_slash = $(srctree)/
 endif
 
-
-HOSTCFLAGS_usage.o = -I$(srctree_slash)include
+HOSTCFLAGS_usage.o = -I$(srctree_slash)include -Iinclude
+HOSTCFLAGS_usage_pod.o = -I$(srctree_slash)include -Iinclude
 
 applets/applets.o: include/usage_compressed.h include/applet_tables.h
 
-applets/usage:         .config $(srctree_slash)applets/usage_compressed
 applets/applet_tables: .config
+applets/usage:         .config
+applets/usage_pod:     .config include/applet_tables.h
 
 quiet_cmd_gen_usage_compressed = GEN     include/usage_compressed.h
       cmd_gen_usage_compressed = $(srctree_slash)applets/usage_compressed include/usage_compressed.h applets
diff --git a/applets/applet_tables.c b/applets/applet_tables.c
index 17135ddc1..e67f017e7 100644
--- a/applets/applet_tables.c
+++ b/applets/applet_tables.c
@@ -70,29 +70,32 @@ int main(int argc, char **argv)
 
 	/* Keep in sync with include/busybox.h! */
 
-	puts("/* This is a generated file, don't edit */\n");
+	printf("/* This is a generated file, don't edit */\n\n");
 
 	printf("#define NUM_APPLETS %u\n", NUM_APPLETS);
 	if (NUM_APPLETS == 1) {
 		printf("#define SINGLE_APPLET_STR \"%s\"\n", applets[0].name);
 		printf("#define SINGLE_APPLET_MAIN %s_main\n", applets[0].name);
 	}
+	printf("\n");
 
-	puts("\nconst char applet_names[] ALIGN1 = \"\"");
+	printf("const char applet_names[] ALIGN1 = \"\"\n");
 	for (i = 0; i < NUM_APPLETS; i++) {
 		printf("\"%s\" \"\\0\"\n", applets[i].name);
 		if (MAX_APPLET_NAME_LEN < strlen(applets[i].name))
 			MAX_APPLET_NAME_LEN = strlen(applets[i].name);
 	}
-	puts(";");
+	printf(";\n\n");
 
-	puts("\nint (*const applet_main[])(int argc, char **argv) = {");
+	printf("#ifndef SKIP_applet_main\n");
+	printf("int (*const applet_main[])(int argc, char **argv) = {\n");
 	for (i = 0; i < NUM_APPLETS; i++) {
 		printf("%s_main,\n", applets[i].main);
 	}
-	puts("};");
+	printf("};\n");
+	printf("#endif\n\n");
 
-	puts("const uint16_t applet_nameofs[] ALIGN2 = {");
+	printf("const uint16_t applet_nameofs[] ALIGN2 = {\n");
 	for (i = 0; i < NUM_APPLETS; i++) {
 		printf("0x%04x,\n",
 			offset[i]
@@ -105,10 +108,10 @@ int main(int argc, char **argv)
 #endif
 		);
 	}
-	puts("};");
+	printf("};\n\n");
 
 #if ENABLE_FEATURE_INSTALLER
-	puts("const uint8_t applet_install_loc[] ALIGN1 = {");
+	printf("const uint8_t applet_install_loc[] ALIGN1 = {\n");
 	i = 0;
 	while (i < NUM_APPLETS) {
 		int v = applets[i].install_loc; /* 3 bits */
@@ -117,7 +120,7 @@ int main(int argc, char **argv)
 		printf("0x%02x,\n", v);
 		i++;
 	}
-	puts("};\n");
+	printf("};\n\n");
 #endif
 
 	printf("#define MAX_APPLET_NAME_LEN %u\n", MAX_APPLET_NAME_LEN);
diff --git a/applets/usage.c b/applets/usage.c
index 1e038b367..d4fd12f9b 100644
--- a/applets/usage.c
+++ b/applets/usage.c
@@ -8,17 +8,17 @@
 
 /* Just #include "autoconf.h" doesn't work for builds in separate
  * object directory */
-#include "../include/autoconf.h"
+#include "autoconf.h"
 
 /* Since we can't use platform.h, have to do this again by hand: */
 #if ENABLE_NOMMU
-#define BB_MMU 0
-#define USE_FOR_NOMMU(...) __VA_ARGS__
-#define USE_FOR_MMU(...)
+# define BB_MMU 0
+# define USE_FOR_NOMMU(...) __VA_ARGS__
+# define USE_FOR_MMU(...)
 #else
-#define BB_MMU 1
-#define USE_FOR_NOMMU(...)
-#define USE_FOR_MMU(...) __VA_ARGS__
+# define BB_MMU 1
+# define USE_FOR_NOMMU(...)
+# define USE_FOR_MMU(...) __VA_ARGS__
 #endif
 
 static const char usage_messages[] = ""
diff --git a/applets/usage_pod.c b/applets/usage_pod.c
new file mode 100644
index 000000000..058e0c842
--- /dev/null
+++ b/applets/usage_pod.c
@@ -0,0 +1,97 @@
+/* vi: set sw=4 ts=4: */
+/*
+ * Copyright (C) 2009 Denys Vlasenko.
+ *
+ * Licensed under GPLv2, see file LICENSE in this tarball for details.
+ */
+#include <unistd.h>
+#include <stdint.h>
+#include <string.h>
+#include <stdio.h>
+
+/* Just #include "autoconf.h" doesn't work for builds in separate
+ * object directory */
+#include "autoconf.h"
+
+#define SKIP_applet_main
+#define ALIGN1 /* nothing, just to placate applet_tables.h */
+#define ALIGN2 /* nothing, just to placate applet_tables.h */
+#include "applet_tables.h"
+
+/* Since we can't use platform.h, have to do this again by hand: */
+#if ENABLE_NOMMU
+# define BB_MMU 0
+# define USE_FOR_NOMMU(...) __VA_ARGS__
+# define USE_FOR_MMU(...)
+#else
+# define BB_MMU 1
+# define USE_FOR_NOMMU(...)
+# define USE_FOR_MMU(...) __VA_ARGS__
+#endif
+
+static const char usage_messages[] = ""
+#define MAKE_USAGE
+#include "usage.h"
+#include "applets.h"
+;
+
+int main(void)
+{
+	const char *names;
+	const char *usage;
+	int col, len2;
+
+	col = 0;
+	names = applet_names;
+	while (*names) {
+		len2 = strlen(names) + 2;
+		if (col >= 76 - len2) {
+			printf(",\n");
+			col = 0;
+		}
+		if (col == 0) {
+			col = 6;
+			printf("\t");
+		} else {
+			printf(", ");
+		}
+		printf(names);
+		col += len2;
+		names += len2 - 1;
+	}
+	printf("\n\n");
+
+	printf("=head1 COMMAND DESCRIPTIONS\n\n");
+	printf("=over 4\n\n");
+
+	names = applet_names;
+	usage = usage_messages;
+	while (*names && usage) {
+		if (*names >= 'a' && *names <= 'z'
+		 && *usage != NOUSAGE_STR[0]
+		) {
+			printf("=item B<%s>\n\n", names);
+			printf("%s %s\n\n", names, usage);
+		}
+		names += strlen(names) + 1;
+		usage += strlen(usage) + 1;
+	}
+	return 0;
+}
+
+/* TODO: we used to make options bold with B<> and output an example too:
+
+=item B<cat>
+
+cat [B<-u>] [FILE]...
+
+Concatenate FILE(s) and print them to stdout
+
+Options:
+        -u      Use unbuffered i/o (ignored)
+
+Example:
+        $ cat /proc/uptime
+        110716.72 17.67
+
+*/