add basic library support

5 files changed, 70 insertions, 25 deletions

diff --git a/README.md b/README.md
index 4db8cff..b9e9f4f 100644
--- a/README.md
+++ b/README.md
@@ -10,13 +10,9 @@ There are a few restrictions:
 
 - Source files must be named ending with .c.
 
-- Only executables are supported, not libraries (there must be a main()).
-
-- Only one executable per source tree is supported (exactly one main()).
-
-- Maje expects the resulting binary to have the same base name as the source
-file containing main() (e.g. if main() is in maje.c, the binary will be called
-maje).
+- Only one target per source tree: a binary (identified by the source file
+  containing main(), which will have the same basename without .c), or a
+  library (identified by the MAJE_LIB flag (see below).
 
 Usage
 =====
@@ -56,6 +52,8 @@ up to the first white space character as indicated:
     MAJE_CFLAG		Added to the CFLAGS macro
     MAJE_LDFLAG		Added to the LDFLAGS macro
     MAJE_LDLIB		Added to the LDLIBS macro
+    MAJE_LIB		Used as the library basename (e.g. MAJE_LIB=foo
+				will create libfoo.a and libfoo.so)
 
 Maje will find these strings anywhere in your source file, so long as they
 are followed by an equal sign, one or more characters, and a whitespace
diff --git a/list.c b/list.c
index 2fa06ab..46d36a5 100644
--- a/list.c
+++ b/list.c
@@ -49,6 +49,8 @@ struct majeflag *insert_flag(struct majeflag *list, char *flag)
 		type = MAJE_LDFLAG;
 	} else if (!strcmp(flag, "MAJE_LDLIB")) {
 		type = MAJE_LDLIB;
+	} else if (!strcmp(flag, "MAJE_LIB")) {
+		type = MAJE_LIB;
 	} else {
 		fprintf(stderr, "maje: unkonwn directive '%s'\n", flag);
 		return list;
diff --git a/maje.c b/maje.c
index c67af52..a449d17 100644
--- a/maje.c
+++ b/maje.c
@@ -42,13 +42,12 @@ int main(int argc, char *argv[])
 
 	struct majefile *sources = find_source_files(srcdir);
 	char *mainname = find_main(sources);
-	if (!mainname) {
-		printf("libraries not yet supported\n");
-		return 0;
+	char *target = NULL;
+	if (mainname) {
+		target = strdup(mainname);
+		target[strlen(target) - 2] = '\0';
+		target = basename(target);
 	}
-	char *target = strdup(mainname);
-	target[strlen(target) - 2] = '\0';
-	target = basename(target);
 
 	FILE *makefile = fopen("Makefile", "w");
 	if (makefile == NULL) {
diff --git a/maje.h b/maje.h
index ae62e0e..920efa5 100644
--- a/maje.h
+++ b/maje.h
@@ -13,7 +13,7 @@ struct majefile {
 struct majeflag {
 	struct majeflag *next;
 	struct majeflag *prev;
-	enum { MAJE_CFLAG, MAJE_LDFLAG, MAJE_LDLIB } type;
+	enum { MAJE_CFLAG, MAJE_LDFLAG, MAJE_LDLIB, MAJE_LIB } type;
 	char flag[];
 };
 
diff --git a/make.c b/make.c
index 13bc7eb..80c2eba 100644
--- a/make.c
+++ b/make.c
@@ -6,7 +6,7 @@
 
 #include "maje.h"
 
-static void make_header(FILE *makefile, const char *target, struct majeflag *flags)
+static void make_header(FILE *makefile, const char *target, struct majeflag *flags, int lib)
 {
 	fprintf(makefile, ".POSIX:\n\n");
 	fprintf(makefile, "# This Makefile was generated by maje\n");
@@ -43,26 +43,43 @@ static void make_header(FILE *makefile, const char *target, struct majeflag *fla
 	fprintf(makefile, "SRCDIR=.\n");
 	fprintf(makefile, "OBJDIR=.\n");
 	fprintf(makefile, "BINDIR=$(OBJDIR)\n");
+	fprintf(makefile, "LIBDIR=$(OBJDIR)\n");
 	fprintf(makefile, "DESTDIR=/usr/local\n");
 	fprintf(makefile, "\n");
 
-	fprintf(makefile, "all: $(BINDIR)/%s\n\n", target);
+	fprintf(makefile, "all: ");
+	if (lib) {
+		fprintf(makefile, "$(LIBDIR)/lib%s.a $(LIBDIR)/lib%s.so", target, target);
+	} else {
+		fprintf(makefile, "$(BINDIR)/%s", target);
+	}
+	fprintf(makefile, "\n\n");
 
 	fprintf(makefile, "clean:\n");
 	fprintf(makefile, "\trm -f $(BINDIR)/%s $(OBJDIR)/*.o\n\n", target);
 
 	fprintf(makefile, "install: $(BINDIR)/%s\n", target);
-	fprintf(makefile, "\tmkdir -p $(DESTDIR)/bin\n");
-	fprintf(makefile, "\tcp $(BINDIR)/%s $(DESTDIR)/bin\n\n", target);
+	if (lib) {
+		fprintf(makefile, "\tmkdir -p $(DESTDIR)/lib\n");
+		fprintf(makefile, "\tcp $(LIBDIR)/lib%s.{a,so} $(DESTDIR)/lib\n\n", target);
+	} else {
+		fprintf(makefile, "\tmkdir -p $(DESTDIR)/bin\n");
+		fprintf(makefile, "\tcp $(BINDIR)/%s $(DESTDIR)/bin\n\n", target);
+	}
 }
 
-static void add_object(FILE *makefile, const struct majefile *src, const char *target)
+static void add_object(FILE *makefile, const struct majefile *src, const char *target, int lib)
 {
 	char *fullobj = strdup(src->path);
 	char *obj = basename(fullobj);
 	obj[strlen(obj) - 1] = 'o';
 
-	fprintf(makefile, "$(BINDIR)/%s: $(OBJDIR)/%s\n", target, obj);
+	if (lib) {
+		fprintf(makefile, "$(LIBDIR)/lib%s.a $(LIBDIR)/lib%s.so: $(OBJDIR)/%s\n", target, target, obj);
+	} else {
+		fprintf(makefile, "$(BINDIR)/%s: $(OBJDIR)/%s\n", target, obj);
+	}
+
 	for (struct majefile *inc = find_includes(src); inc != NULL; inc = inc->next) {
 		fprintf(makefile, "$(OBJDIR)/%s: $(SRCDIR)/%s\n",
 			obj, inc->path);
@@ -87,14 +104,43 @@ void make_makefile(const char *makepath, struct majefile *sources, const char *t
 		flags = add_flags(src, flags);
 	}
 
-	make_header(makefile, target, flags);
+	int lib = 0;
+	if (target == NULL) {
+		lib = 1;
+		for (struct majeflag *flag = flags; flag != NULL; flag = flag->next) {
+			if (flag->type == MAJE_LIB) {
+				if (target) {
+					fprintf(stderr, "maje: only one MAJE_LIB is supported\n");
+					exit(1);
+				}
+				target = flag->flag;
+			}
+		}
+	}
+
+	if (lib == 1 && target == NULL) {
+		fprintf(stderr, "maje: couldn't determine binary or library name\n");
+		exit(1);
+	}
+
+	make_header(makefile, target, flags, lib);
 	for (struct majefile *src = sources; src != NULL; src = src->next) {
-		add_object(makefile, src, target);
+		add_object(makefile, src, target, lib);
 	}
 
-	fprintf(makefile, "$(BINDIR)/%s:\n", target);
-	fprintf(makefile, "\t@mkdir -p $(@D)\n");
-	fprintf(makefile, "\t$(LD) $(LDFLAGS) -o $@ $(OBJDIR)/*.o $(LDLIBS)\n");
+	if (lib) {
+		fprintf(makefile, "$(LIBDIR)/lib%s.a:\n", target);
+		fprintf(makefile, "\t@mkdir -p $(@D)\n");
+		fprintf(makefile, "\t$(AR) $(ARFLAGS) $@ $(OBJDIR)/*.o\n\n");
+
+		fprintf(makefile, "$(LIBDIR)/lib%s.so:\n", target);
+		fprintf(makefile, "\t@mkdir -p $(@D)\n");
+		fprintf(makefile, "\t$(LD) -shared $(LDFLAGS) -o $@ $(OBJDIR)/*.o $(LDLIBS)\n\n");
+	} else {
+		fprintf(makefile, "$(BINDIR)/%s:\n", target);
+		fprintf(makefile, "\t@mkdir -p $(@D)\n");
+		fprintf(makefile, "\t$(LD) $(LDFLAGS) -o $@ $(OBJDIR)/*.o $(LDLIBS)\n");
+	}
 
 	fclose(makefile);
 }