diff options
Diffstat (limited to 'recipes/opkg/files/opkg_wget_nogpg_01_use_vfork_gunzip.patch')
| -rw-r--r-- | recipes/opkg/files/opkg_wget_nogpg_01_use_vfork_gunzip.patch | 163 |
1 files changed, 163 insertions, 0 deletions
diff --git a/recipes/opkg/files/opkg_wget_nogpg_01_use_vfork_gunzip.patch b/recipes/opkg/files/opkg_wget_nogpg_01_use_vfork_gunzip.patch new file mode 100644 index 0000000000..00bd0bdd29 --- /dev/null +++ b/recipes/opkg/files/opkg_wget_nogpg_01_use_vfork_gunzip.patch @@ -0,0 +1,163 @@ +# This patchset updates the libbb stuff to use a vfork() version of +# gz_open, called gzvopen. This is done because a standard fork will +# duplicate the entire address space. This will invoke the OOM +# (out of memory) killer on small-memory machines, because most often +# by the time we unzip any package, we've read the entire package +# database into memory already. By using vfork() and immediatly +# execing the external gunzip utility, we avoid the need to clone the +# entire address space. +# +# Yes, this is actually **LESS** efficient than the original way! +# But there is no way to (currently) dodge the OOM killer on a +# per-process basis, so the alternatives are to either change the +# OOM killer behavior system-wide, or to use this workaround. +# +# Mike Westerhof, Dec 2008 + +--- orig/libbb/gz_open.c 2008-03-01 12:55:33.000000000 -0600 ++++ opkg/libbb/gz_open.c 2008-12-21 21:41:13.000000000 -0600 +@@ -56,3 +56,78 @@ + } + return(fdopen(unzip_pipe[0], "r")); + } ++ ++/* gz_open implementation using gunzip and a vfork/exec -- dodges OOM killer */ ++extern FILE *gzvopen(FILE *compressed_file, int *pid) ++{ ++ int unzip_pipe[2]; ++ off_t floc; ++ int cfile; ++ ++ /* create a new file descriptor for the input stream ++ * (it *must* be associated with a file) ++ * and seek to the same position in that fd as the stream. ++ */ ++ cfile = dup(fileno(compressed_file)); ++ floc = ftello(compressed_file); ++ lseek(cfile, floc, SEEK_SET); ++ ++ /* create the pipe */ ++ if (pipe(unzip_pipe)!=0) { ++ error_msg("gzvopen(): pipe error"); ++ return(NULL); ++ } ++ ++ *pid = vfork(); ++ ++ if (*pid < 0) { ++ error_msg("gzvopen(): fork failed"); ++ return(NULL); ++ } ++ ++ if (*pid==0) { ++ /* child process - reads STDIN, writes to pipe */ ++ ++ /* close unused read end of pipe */ ++ close(unzip_pipe[0]); ++ ++ /* connect child's stdout to the pipe write end */ ++ dup2(unzip_pipe[1], 1); ++ ++ /* connect child's stdin to the fd passed in to us */ ++ dup2(cfile, 0); ++ ++ /* execute the gunzip utility */ ++ execlp("gunzip","gunzip",NULL); ++ ++ /* if we get here, we had a failure - since we are ++ * using vfork(), we cannot call exit(), must call _exit(). ++ */ ++ _exit(-1); ++ } ++ ++ /* Parent process is executing here */ ++ ++ /* we have no more need of the duplicate fd */ ++ close(cfile); ++ ++ /* close the write end of the pipe */ ++ close(unzip_pipe[1]); ++ ++ /* return the read end of the pipe as a FILE */ ++ return(fdopen(unzip_pipe[0], "r")); ++} ++ ++extern void gzvclose(int gunzip_pid) ++{ ++ if (kill(gunzip_pid, SIGTERM) == -1) { ++ perror("gzvclose()"); ++ fprintf(stderr,"%s: unable to kill gunzip pid.\n", ++ __FUNCTION__); ++ } ++ ++ if (waitpid(gunzip_pid, NULL, 0) == -1) { ++ fprintf(stderr,"%s: unable to wait on gunzip pid.\n", ++ __FUNCTION__); ++ } ++} +--- orig/libbb/libbb.h 2008-12-20 15:06:51.000000000 -0600 ++++ opkg/libbb/libbb.h 2008-12-21 21:41:13.000000000 -0600 +@@ -270,6 +270,8 @@ + extern int unzip(FILE *l_in_file, FILE *l_out_file); + extern void gz_close(int gunzip_pid); + extern FILE *gz_open(FILE *compressed_file, int *pid); ++extern void gzvclose(int gunzip_pid); ++extern FILE *gzvopen(FILE *compressed_file, int *pid); + + extern struct hostent *xgethostbyname(const char *name); + extern int create_icmp_socket(void); +--- orig/libbb/unarchive.c 2008-09-10 11:48:23.000000000 -0500 ++++ opkg/libbb/unarchive.c 2008-12-21 21:41:13.000000000 -0600 +@@ -749,7 +749,7 @@ + while ((ar_header = get_header_ar(deb_stream)) != NULL) { + if (strcmp(ared_file, ar_header->name) == 0) { + /* open a stream of decompressed data */ +- uncompressed_stream = gz_open(deb_stream, &gunzip_pid); ++ uncompressed_stream = gzvopen(deb_stream, &gunzip_pid); + archive_offset = 0; + output_buffer = unarchive(uncompressed_stream, out_stream, get_header_tar, free_header_tar, extract_function, prefix, file_list); + } +@@ -757,7 +757,7 @@ + free (ar_header->name); + free (ar_header); + } +- gz_close(gunzip_pid); ++ gzvclose(gunzip_pid); + fclose(deb_stream); + fclose(uncompressed_stream); + free(ared_file); +@@ -769,7 +769,7 @@ + file_header_t *tar_header; + archive_offset = 0; + fseek(deb_stream, 0, SEEK_SET); +- unzipped_opkg_stream = gz_open(deb_stream, &unzipped_opkg_pid); ++ unzipped_opkg_stream = gzvopen(deb_stream, &unzipped_opkg_pid); + + /*fprintf(stderr, __FUNCTION__ ": processing opkg %s -- ared_file=%s\n", package_filename, ared_file);*/ + /* walk through outer tar file to find ared_file */ +@@ -779,7 +779,7 @@ + name_offset = 2; + if (strcmp(ared_file, tar_header->name+name_offset) == 0) { + /* open a stream of decompressed data */ +- uncompressed_stream = gz_open(unzipped_opkg_stream, &gunzip_pid); ++ uncompressed_stream = gzvopen(unzipped_opkg_stream, &gunzip_pid); + archive_offset = 0; + /*fprintf(stderr, __FUNCTION__ ":%d: here -- found file\n", __LINE__);*/ + output_buffer = unarchive(uncompressed_stream, +@@ -791,14 +791,14 @@ + file_list); + /*fprintf(stderr, __FUNCTION__ ":%d: unarchive complete\n", __LINE__);*/ + free_header_tar(tar_header); +- gz_close(gunzip_pid); ++ gzvclose(gunzip_pid); + fclose(uncompressed_stream); + break; + } + seek_sub_file(unzipped_opkg_stream, tar_header->size); + free_header_tar(tar_header); + } +- gz_close(unzipped_opkg_pid); ++ gzvclose(unzipped_opkg_pid); + fclose(unzipped_opkg_stream); + fclose(deb_stream); + free(ared_file); |