README.md: improve markup

Do not try to load symbols from VDSO as it does not correspond to any
file on disk.

.cvsignore

@@ -1 +0,0 @@
-pstack

.gitattributes

@@ -0,0 +1,2 @@
+.gitignore export-ignore
+.gitattributes export-ignore

Makefile

@@ -15,33 +15,37 @@
 #
 
 VERSION = $(shell awk 'END { print $$1 }' VERSION)
-CFLAGS = -Wall -DVERSION=\"$(VERSION)\" $(RPM_OPT_FLAGS)
+CFLAGS ?= -Wall -Wextra -g -O2
+CPPFLAGS += -DVERSION=\"$(VERSION)\"
+
+# Note: assignments are ignored for variable overriden on command line VAR=value
+# so DESTDIR is ignored for overriden variables
+PREFIX ?= /usr
+BINDIR ?= $(PREFIX)/bin
+BINDIR := $(DESTDIR)$(BINDIR)
+MANDIR ?= $(PREFIX)/share/man
+MANDIR := $(DESTDIR)$(MANDIR)
 
-ifeq ($(RPM_OPT_FLAGS),)
-CFLAGS += -g
-LDFLAGS += -g
-endif
 
 pstack : pstack.c
-	$(CC) $(CFLAGS) -o pstack pstack.c
+	$(CC) $(CPPFLAGS) $(CFLAGS) -o pstack $^ $(LDFLAGS)
 
 clean:
 	rm -f pstack
 
 install : pstack
-	mkdir -p $(BINDIR)
-	install -m 755 pstack $(BINDIR)
-	mkdir -p $(MANDIR)/man1
-	install -m 644 man1/pstack.1 $(MANDIR)/man1
+	mkdir -p "$(BINDIR)"
+	install -m 755 pstack "$(BINDIR)"
+	mkdir -p "$(MANDIR)/man1"
+	install -m 644 man1/pstack.1 "$(MANDIR)/man1"
 
-cvstag:
-	cvs tag -F $(CVSTAG) .
+gittag:
+	git tag -s pstack-$(VERSION)
 
-archive: cvstag
-	@rm -rf /tmp/pstack-$(VERSION) /tmp/pstack
-	@cd /tmp; cvs export -r$(CVSTAG) pstack; mv pstack pstack-$(VERSION)
-	@cd /tmp; tar czSpf pstack-$(VERSION).tar.gz pstack-$(VERSION)
-	@rm -rf /tmp/pstack-$(VERSION)
+archive: gittag
+	@rm -rf /tmp/pstack-$(VERSION).tar.gz
+	@git archive -o /tmp/pstack-$(VERSION).tar --prefix=pstack-$(VERSION)/ pstack-$(VERSION)
+	@cd /tmp; gzip -9 pstack-$(VERSION).tar
 	@cp /tmp/pstack-$(VERSION).tar.gz .
-	@echo " "
+	@echo ""
 	@echo "The final archive is ./pstack-$(VERSION).tar.gz."

README.md

@@ -1,4 +1,4 @@
-pstack - print stack trace of running processes
+# pstack - print stack trace of running processes
 
 pstack dumps a stack trace for a process, given the pid of that
 process.  If the process named is part of a thread group, then all the threads
@@ -6,8 +6,9 @@ inthe group are traced.  See the man page for more information.
 
 This program was inspired by the 'pstack' program available on Solaris.
 
-SUPPORTED PLATFORMS:
-	This program runs on 32 bit x86 machines, using ELF binaries
+## Supported Platforms
+
+This program runs on 32 bit x86 machines, using ELF binaries
 generated from GNU compilers.  If threads are being used, it depends
 on a debuggable version of the pthreads library to find the threads in
 the thread group.  If anyone wants to port this to other
@@ -15,22 +16,20 @@ architectures, please let me know about questions you may have, or
 achievements you have made.  I'd like to incorporate such changes into
 my version of the code.
 
-FEATURES:
-	symbolic address dumping
-  thread group support
+## Features
 
-BUILD:
-   make
+* symbolic address dumping
+* thread group support
 
-INSTALL:
-	 make install
+## Build, install, uninstall
 
-UNINSTALL:
-   make uninstall
+    make
+    make install
+    make uninstall
 
-NOTE: you must be root to [un]install.  pstack will run fine from any
+**Note:** you must be root to [un]install. pstack will run fine from any
 directory, install just puts the binary and man page in 'normal'
-places (/usr/local/...)
+places (`/usr/local/...`)
 
 USAGE:
 	pstack pid [...]

VERSION

@@ -2,3 +2,4 @@
 1.1 25/Feb/2002
 1.2 12/Nov/2003
 1.3 02/Oct/2011
+1.3.1 03/Oct/2011

changelog

@@ -1,3 +1,17 @@
+** pstack 1.3.1 **
+
+Thomas Preud'homme (6):
+      Fix incorrect ptrace failure tests in crawl()
+      Add -Wextra flags to CFLAGS and fix warnings
+      Remove distribution specific variables in Makefile
+      Respect CFLAGS from the environment
+      Support DESTDIR and PREFIX variables in Makefile
+      Rewrite archive and cvstag make rules for git
+      Don't include .*ignore files in archives
+      Compile with -g -O2 by default
+      Make struct used by PTRACE_GETREGS arch-dependant
+      Error out if no object file header
+
 ** pstack 1.3 **
 
 Baruch Even (1):
@@ -15,4 +29,3 @@ Thomas Preud'homme (12):
       Add support for armel architecture
       Include <endian.h> as fallback for endianness
       Do not call perror in crawl() if no ptrace error
-

pstack.c

@@ -66,6 +66,7 @@
 #define ElfN_Addr Elf64_Addr
 #define ElfN_Sym Elf64_Sym
 #define ElfN_Dyn Elf64_Dyn
+#define ElfN_Off Elf64_Off
 #define ELFCLASSN ELFCLASS64
 #define ELFN_ST_TYPE ELF64_ST_TYPE
 #define INT_RANGE_STR "64"
@@ -76,6 +77,7 @@
 #define ElfN_Addr Elf32_Addr
 #define ElfN_Sym Elf32_Sym
 #define ElfN_Dyn Elf32_Dyn
+#define ElfN_Off Elf32_Off
 #define ELFCLASSN ELFCLASS32
 #define ELFN_ST_TYPE ELF32_ST_TYPE
 #define INT_RANGE_STR "32"
@@ -112,12 +114,16 @@
 #endif /* x86-{32,64} */
 #define NEXT_FRAME_POINTER_ADDR(fp) (fp)
 #define NEXT_PROGRAM_COUNTER_ADDR(fp) ((fp) + __SIZEOF_POINTER__)
+#define DECLARE_REGS_STRUCT(regs) struct user_regs_struct regs
+#define VDSO_NAME "linux-vdso.so.1"
 #elif defined(__ARMEL__) /* armel */
 #define ELF_MACHINE EM_ARM
 #define PROGRAM_COUNTER(regs) (regs.ARM_pc)
 #define FRAME_POINTER(regs) (regs.ARM_fp)
 #define NEXT_FRAME_POINTER_ADDR(fp) ((fp) - __SIZEOF_POINTER__)
 #define NEXT_PROGRAM_COUNTER_ADDR(fp) (fp)
+#define DECLARE_REGS_STRUCT(regs) struct user_regs regs
+#define VDSO_NAME ""
 #elif defined(__ppc64__) || defined(__alpha__) || defined(__ia64__) || defined(s390x__)
 #error Not (yet) supported architecture, patches welcomes :-)
 #else
@@ -280,7 +286,7 @@ static void findCodeAddress(ElfN_Addr addr, ElfN_Sym **ans,
 {
   ElfN_Sym *sym;
   Symbols tab;
-  uintN_t i;
+  int i;
 
   for (tab = allSyms, *ans = 0, *symtab = 0; tab; tab = tab->next) {
     if (addr < tab->baseAddr) continue;
@@ -370,7 +376,7 @@ static void checkForThreads(Symbols syms, int pid)
     if (!descr && i == 0)
       /* The initial thread's descriptor was not initialized yet.  */
       *pptr++ = pid;
-    else if (descr != -1 || !errno) {
+    else if (descr != (ElfN_Addr) -1 || !errno) {
       tpid = ptrace(PTRACE_PEEKDATA, pid, descr + pidOff, 0);
       if (tpid != -1 || !errno)
         *pptr++ = tpid;
@@ -438,8 +444,8 @@ static int find_stables(ElfN_Ehdr *hdr, int fd, Symbols syms)
       if (!(syms->symbols = (ElfN_Sym *) malloc(shdr.sh_size)))
         quit("Could not allocate symbol table.");
 
-      if (lseek(fd, shdr.sh_offset, SEEK_SET) != shdr.sh_offset ||
-          read(fd, syms->symbols, shdr.sh_size) != shdr.sh_size)
+      if ((ElfN_Off) lseek(fd, shdr.sh_offset, SEEK_SET) != shdr.sh_offset ||
+          (uintN_t) read(fd, syms->symbols, shdr.sh_size) != shdr.sh_size)
         quit("Could not read symbol table.");
 
       i = hdr->e_shoff + shdr.sh_link * hdr->e_shentsize;
@@ -449,8 +455,8 @@ static int find_stables(ElfN_Ehdr *hdr, int fd, Symbols syms)
         quit("Could not read string table section header.");
       if (!(syms->strings = malloc(shdr.sh_size)))
         quit("Could not allocate string table.");
-      if (lseek(fd, shdr.sh_offset, SEEK_SET) != shdr.sh_offset ||
-          read(fd, syms->strings, shdr.sh_size) != shdr.sh_size)
+      if ((ElfN_Off) lseek(fd, shdr.sh_offset, SEEK_SET) != shdr.sh_offset ||
+          (uintN_t) read(fd, syms->strings, shdr.sh_size) != shdr.sh_size)
         quit("Could not read string table.");
       lseek(fd, spot, SEEK_SET);
       break;
@@ -458,8 +464,8 @@ static int find_stables(ElfN_Ehdr *hdr, int fd, Symbols syms)
       syms->ndyns = shdr.sh_size / sizeof(ElfN_Dyn);
       if (!(syms->dynamic = (ElfN_Dyn *) malloc(shdr.sh_size)))
         quit("Out of memory.");
-      if (lseek(fd, shdr.sh_offset, SEEK_SET) != shdr.sh_offset ||
-          read(fd, syms->dynamic, shdr.sh_size) != shdr.sh_size)
+      if ((ElfN_Off) lseek(fd, shdr.sh_offset, SEEK_SET) != shdr.sh_offset ||
+          (uintN_t) read(fd, syms->dynamic, shdr.sh_size) != shdr.sh_size)
         quit("Could not read dynamic table.");
       lseek(fd, spot, SEEK_SET);
       break;
@@ -477,6 +483,8 @@ static Symbols loadSyms(const char *fname)
 
   if (*fname == '\0')
     return (Symbols) 0;
+  if (!strcmp(VDSO_NAME, fname))
+    return (Symbols) 0;
   syms = newSyms(fname);
   if ((fd = open(fname, O_RDONLY)) < 0)
   {
@@ -484,7 +492,12 @@ static Symbols loadSyms(const char *fname)
     perror("opening object file");
     quit("Could not open object file.");
   }
-  read(fd, &hdr, sizeof(hdr));
+  if (read(fd, &hdr, sizeof(hdr)) < (int) sizeof(hdr))
+  {
+    fprintf(stderr, "'%s': ", fname);
+    perror("reading object file ELF header");
+    quit("Could not read object file ELF header.");
+  }
   verify_ident(&hdr);
   if (!find_stables(&hdr, fd, syms)) {
     deleteSyms(syms);
@@ -542,16 +555,17 @@ static void resolveSymbols(Symbols syms, int offset)
   }
 }
 
-static void loadString(pid_t pid, ElfN_Addr addr, char *dp, int bytes)
+static void loadString(pid_t pid, ElfN_Addr addr, char *dp, unsigned int bytes)
 {
-  long *lp = (long *) dp, nr;
+  long *lp = (long *) dp;
+  unsigned int nr;
   int error_occured = 0;
 
   memset(dp, 0, bytes);
   errno = 0;
 
   addr = ptrace(PTRACE_PEEKDATA, pid, addr, 0);
-  if (addr == -1 && errno)
+  if (addr == (ElfN_Addr) -1 && errno)
     error_occured = 0;
 
   for (nr = 0; bytes > sizeof(long) && strlen(dp) == nr;
@@ -571,7 +585,7 @@ static void loadString(pid_t pid, ElfN_Addr addr, char *dp, int bytes)
 }
 
 static void readLinkMap(int pid, ElfN_Addr base,
-                        struct link_map *lm, char *name, int namelen)
+                        struct link_map *lm, char *name, unsigned int namelen)
 {
   /* base address */
   lm->l_addr = (ElfN_Addr) ptrace(PTRACE_PEEKDATA, pid,
@@ -640,12 +654,12 @@ static int crawl(int pid)
 {
   unsigned long pc, fp, nextfp, nargs, i, arg;
   int ret, error_occured = 0;
-  struct pt_regs regs;
+  DECLARE_REGS_STRUCT(regs);
 
   errno = 0;
 
   ret = ptrace(PTRACE_GETREGS, pid, NULL, &regs);
-  if (ret != -1 && !errno) {
+  if (ret != -1) {
     pc = PROGRAM_COUNTER(regs);
     fp = FRAME_POINTER(regs);
   }
@@ -656,7 +670,7 @@ static int crawl(int pid)
     print_pc(pc);
     for ( ; !error_occured && fp; ) {
       nextfp = ptrace(PTRACE_PEEKDATA, pid, NEXT_FRAME_POINTER_ADDR(fp), 0);
-      if (nextfp == (unsigned) -1 && errno) {
+      if (nextfp == (unsigned long) -1 && errno) {
         error_occured = 1;
         break;
       }
@@ -667,7 +681,7 @@ static int crawl(int pid)
         fputs(" (", stdout);
         for (i = 1; i <= nargs; i++) {
           arg = ptrace(PTRACE_PEEKDATA, pid, ARG_NMBR(fp,i), 0);
-          if (arg == (unsigned) -1 && errno) {
+          if (arg == (unsigned long) -1 && errno) {
             error_occured = 1;
             break;
           }
@@ -682,7 +696,7 @@ static int crawl(int pid)
 
       if (error_occured || !nextfp) break;
       pc = ptrace(PTRACE_PEEKDATA, pid, NEXT_PROGRAM_COUNTER_ADDR(fp), 0);
-      if (pc == (unsigned) -1 && errno) {
+      if (pc == (unsigned long) -1 && errno) {
         error_occured = 1;
         break;
       }
@@ -710,7 +724,7 @@ static char *cmdLine(int pid)
     for (i = 0; i < len; i++) if (!cmd[i]) cmd[i] = ' ';
     for ( ; len > 0 && cmd[len - 1] <= ' '; len--);
     cmd[len] = 0;
-    if (len >= sizeof(cmd) - 4)
+    if ((unsigned int) len >= sizeof(cmd) - 4)
       strcpy(&cmd[sizeof(cmd) - 4], "...");
   } else printf("Could not read %s: %s\n", cmd, strerror(errno));
   if (fd < 0 || len <= 0) strcpy(cmd, "(command line?)");
@@ -729,6 +743,7 @@ void usage(const char *argv0, const char *param)
 int main(int argc, char **argv)
 {
   int i;
+  long thePidTmp;
   const char *argv0 = argv[0];
 
   /* Arrange to detach if we get an unexpected signal.  This prevents
@@ -741,10 +756,11 @@ int main(int argc, char **argv)
 
   for (argc--, argv++; argc > 0; argc--, argv++) {
     char *endptr = NULL;
-    thePid = strtol(*argv, &endptr, 0);
+    thePidTmp = strtol(*argv, &endptr, 0);
     if (!*argv || *endptr || (errno == ERANGE &&
-	    (thePid == LONG_MIN || thePid == LONG_MAX)))
+	    (thePidTmp == LONG_MIN || thePidTmp == LONG_MAX)))
 	    usage(argv0, *argv);
+    thePid = thePidTmp;
     if (!thePid || thePid == getpid()) {
       fprintf(stderr, "Invalid PID %d\n", thePid);
       continue;