Re: [PATCH 9] installboot: malloc/memset = calloc
Commited. Thanks. On Sun, 1 Jun 2014, Benjamin Baier wrote: On Sun, 1 Jun 2014 00:57:43 +1000 Joel Sing j...@sing.id.au wrote: In this case I think readability wins. I do not believe that there is a lot to gain from overflow protection given the numbers used in these calculations are very small (and many are already bounds checked in some form or other). Well, I had to ask. Here is option 2. Index: bootstrap.c === RCS file: /cvs/src/usr.sbin/installboot/bootstrap.c,v retrieving revision 1.3 diff -u -p -r1.3 bootstrap.c --- bootstrap.c 28 Dec 2013 12:01:33 - 1.3 +++ bootstrap.c 31 May 2014 18:14:56 - @@ -68,10 +68,9 @@ bootstrap(int devfd, char *dev, char *bo fprintf(stderr, bootstrap is %zu bytes (%zu sectors @ %u bytes = %zu bytes)\n, (ssize_t)sb.st_size, bootsec, dl.d_secsize, bootsize); - boot = malloc(bootsize); + boot = calloc(1, bootsize); if (boot == NULL) - err(1, malloc); - memset(boot, 0, bootsize); + err(1, calloc); if (read(fd, boot, bootsize) != (ssize_t)sb.st_size) err(1, read); close(fd); Index: i386_softraid.c === RCS file: /cvs/src/usr.sbin/installboot/i386_softraid.c,v retrieving revision 1.1 diff -u -p -r1.1 i386_softraid.c --- i386_softraid.c 19 Jan 2014 02:58:50 - 1.1 +++ i386_softraid.c 31 May 2014 18:14:56 - @@ -129,11 +129,10 @@ sr_install_bootldr(int devfd, char *dev) inodeblk = nblocks - 1; bootsize = nblocks * SR_FS_BLOCKSIZE; - p = malloc(bootsize); + p = calloc(1, bootsize); if (p == NULL) err(1, NULL); - memset(p, 0, bootsize); fd = open(stage2, O_RDONLY, 0); if (fd == -1) err(1, NULL); Index: sparc64_installboot.c === RCS file: /cvs/src/usr.sbin/installboot/sparc64_installboot.c,v retrieving revision 1.1 diff -u -p -r1.1 sparc64_installboot.c --- sparc64_installboot.c 19 Jan 2014 02:58:50 - 1.1 +++ sparc64_installboot.c 31 May 2014 18:14:56 - @@ -68,10 +68,9 @@ md_loadboot(void) if (blksize SBSIZE - DEV_BSIZE) errx(1, boot blocks too big (%zu %d), blksize, SBSIZE - DEV_BSIZE); - blkstore = malloc(blksize); + blkstore = calloc(1, blksize); if (blkstore == NULL) - err(1, malloc); - memset(blkstore, 0, blksize); + err(1, calloc); if (read(fd, blkstore, sb.st_size) != (ssize_t)sb.st_size) err(1, read); close(fd); -- Action without study is fatal. Study without action is futile. -- Mary Ritter Beard
Re: [PATCH 9] installboot: malloc/memset = calloc
bump. anybody? On Sat, 31 May 2014 20:29:42 +0200 Benjamin Baier program...@netzbasis.de wrote: On Sun, 1 Jun 2014 00:57:43 +1000 Joel Sing j...@sing.id.au wrote: In this case I think readability wins. I do not believe that there is a lot to gain from overflow protection given the numbers used in these calculations are very small (and many are already bounds checked in some form or other). Well, I had to ask. Here is option 2. Index: bootstrap.c === RCS file: /cvs/src/usr.sbin/installboot/bootstrap.c,v retrieving revision 1.3 diff -u -p -r1.3 bootstrap.c --- bootstrap.c 28 Dec 2013 12:01:33 - 1.3 +++ bootstrap.c 31 May 2014 18:14:56 - @@ -68,10 +68,9 @@ bootstrap(int devfd, char *dev, char *bo fprintf(stderr, bootstrap is %zu bytes (%zu sectors @ %u bytes = %zu bytes)\n, (ssize_t)sb.st_size, bootsec, dl.d_secsize, bootsize); - boot = malloc(bootsize); + boot = calloc(1, bootsize); if (boot == NULL) - err(1, malloc); - memset(boot, 0, bootsize); + err(1, calloc); if (read(fd, boot, bootsize) != (ssize_t)sb.st_size) err(1, read); close(fd); Index: i386_softraid.c === RCS file: /cvs/src/usr.sbin/installboot/i386_softraid.c,v retrieving revision 1.1 diff -u -p -r1.1 i386_softraid.c --- i386_softraid.c 19 Jan 2014 02:58:50 - 1.1 +++ i386_softraid.c 31 May 2014 18:14:56 - @@ -129,11 +129,10 @@ sr_install_bootldr(int devfd, char *dev) inodeblk = nblocks - 1; bootsize = nblocks * SR_FS_BLOCKSIZE; - p = malloc(bootsize); + p = calloc(1, bootsize); if (p == NULL) err(1, NULL); - memset(p, 0, bootsize); fd = open(stage2, O_RDONLY, 0); if (fd == -1) err(1, NULL); Index: sparc64_installboot.c === RCS file: /cvs/src/usr.sbin/installboot/sparc64_installboot.c,v retrieving revision 1.1 diff -u -p -r1.1 sparc64_installboot.c --- sparc64_installboot.c 19 Jan 2014 02:58:50 - 1.1 +++ sparc64_installboot.c 31 May 2014 18:14:56 - @@ -68,10 +68,9 @@ md_loadboot(void) if (blksize SBSIZE - DEV_BSIZE) errx(1, boot blocks too big (%zu %d), blksize, SBSIZE - DEV_BSIZE); - blkstore = malloc(blksize); + blkstore = calloc(1, blksize); if (blkstore == NULL) - err(1, malloc); - memset(blkstore, 0, blksize); + err(1, calloc); if (read(fd, blkstore, sb.st_size) != (ssize_t)sb.st_size) err(1, read); close(fd);
[PATCH 9] installboot: malloc/memset = calloc
This one splits up the malloc parameter, taking full potential from calloc, hurting readability a bit. which one is preferred? more readable/maintainable or using the calloc overflow protection? Index: bootstrap.c === RCS file: /cvs/src/usr.sbin/installboot/bootstrap.c,v retrieving revision 1.3 diff -u -p -r1.3 bootstrap.c --- bootstrap.c 28 Dec 2013 12:01:33 - 1.3 +++ bootstrap.c 31 May 2014 10:26:27 - @@ -68,10 +68,9 @@ bootstrap(int devfd, char *dev, char *bo fprintf(stderr, bootstrap is %zu bytes (%zu sectors @ %u bytes = %zu bytes)\n, (ssize_t)sb.st_size, bootsec, dl.d_secsize, bootsize); - boot = malloc(bootsize); + boot = calloc(bootsec, dl.d_secsize); if (boot == NULL) - err(1, malloc); - memset(boot, 0, bootsize); + err(1, calloc); if (read(fd, boot, bootsize) != (ssize_t)sb.st_size) err(1, read); close(fd); Index: i386_softraid.c === RCS file: /cvs/src/usr.sbin/installboot/i386_softraid.c,v retrieving revision 1.1 diff -u -p -r1.1 i386_softraid.c --- i386_softraid.c 19 Jan 2014 02:58:50 - 1.1 +++ i386_softraid.c 31 May 2014 10:26:27 - @@ -129,11 +129,10 @@ sr_install_bootldr(int devfd, char *dev) inodeblk = nblocks - 1; bootsize = nblocks * SR_FS_BLOCKSIZE; - p = malloc(bootsize); + p = calloc(nblocks, SR_FS_BLOCKSIZE); if (p == NULL) err(1, NULL); - memset(p, 0, bootsize); fd = open(stage2, O_RDONLY, 0); if (fd == -1) err(1, NULL); Index: sparc64_installboot.c === RCS file: /cvs/src/usr.sbin/installboot/sparc64_installboot.c,v retrieving revision 1.1 diff -u -p -r1.1 sparc64_installboot.c --- sparc64_installboot.c 19 Jan 2014 02:58:50 - 1.1 +++ sparc64_installboot.c 31 May 2014 10:26:27 - @@ -68,10 +68,9 @@ md_loadboot(void) if (blksize SBSIZE - DEV_BSIZE) errx(1, boot blocks too big (%zu %d), blksize, SBSIZE - DEV_BSIZE); - blkstore = malloc(blksize); + blkstore = calloc(blocks, DEV_BSIZE); if (blkstore == NULL) - err(1, malloc); - memset(blkstore, 0, blksize); + err(1, calloc); if (read(fd, blkstore, sb.st_size) != (ssize_t)sb.st_size) err(1, read); close(fd);
Re: [PATCH 9] installboot: malloc/memset = calloc
On Sat, 31 May 2014, Benjamin Baier wrote: This one splits up the malloc parameter, taking full potential from calloc, hurting readability a bit. which one is preferred? more readable/maintainable or using the calloc overflow protection? In this case I think readability wins. I do not believe that there is a lot to gain from overflow protection given the numbers used in these calculations are very small (and many are already bounds checked in some form or other). Index: bootstrap.c === RCS file: /cvs/src/usr.sbin/installboot/bootstrap.c,v retrieving revision 1.3 diff -u -p -r1.3 bootstrap.c --- bootstrap.c 28 Dec 2013 12:01:33 - 1.3 +++ bootstrap.c 31 May 2014 10:26:27 - @@ -68,10 +68,9 @@ bootstrap(int devfd, char *dev, char *bo fprintf(stderr, bootstrap is %zu bytes (%zu sectors @ %u bytes = %zu bytes)\n, (ssize_t)sb.st_size, bootsec, dl.d_secsize, bootsize); - boot = malloc(bootsize); + boot = calloc(bootsec, dl.d_secsize); if (boot == NULL) - err(1, malloc); - memset(boot, 0, bootsize); + err(1, calloc); if (read(fd, boot, bootsize) != (ssize_t)sb.st_size) err(1, read); close(fd); Index: i386_softraid.c === RCS file: /cvs/src/usr.sbin/installboot/i386_softraid.c,v retrieving revision 1.1 diff -u -p -r1.1 i386_softraid.c --- i386_softraid.c 19 Jan 2014 02:58:50 - 1.1 +++ i386_softraid.c 31 May 2014 10:26:27 - @@ -129,11 +129,10 @@ sr_install_bootldr(int devfd, char *dev) inodeblk = nblocks - 1; bootsize = nblocks * SR_FS_BLOCKSIZE; - p = malloc(bootsize); + p = calloc(nblocks, SR_FS_BLOCKSIZE); if (p == NULL) err(1, NULL); - memset(p, 0, bootsize); fd = open(stage2, O_RDONLY, 0); if (fd == -1) err(1, NULL); Index: sparc64_installboot.c === RCS file: /cvs/src/usr.sbin/installboot/sparc64_installboot.c,v retrieving revision 1.1 diff -u -p -r1.1 sparc64_installboot.c --- sparc64_installboot.c 19 Jan 2014 02:58:50 - 1.1 +++ sparc64_installboot.c 31 May 2014 10:26:27 - @@ -68,10 +68,9 @@ md_loadboot(void) if (blksize SBSIZE - DEV_BSIZE) errx(1, boot blocks too big (%zu %d), blksize, SBSIZE - DEV_BSIZE); - blkstore = malloc(blksize); + blkstore = calloc(blocks, DEV_BSIZE); if (blkstore == NULL) - err(1, malloc); - memset(blkstore, 0, blksize); + err(1, calloc); if (read(fd, blkstore, sb.st_size) != (ssize_t)sb.st_size) err(1, read); close(fd); -- Action without study is fatal. Study without action is futile. -- Mary Ritter Beard
Re: [PATCH 9] installboot: malloc/memset = calloc
On Sun, 1 Jun 2014 00:57:43 +1000 Joel Sing j...@sing.id.au wrote: In this case I think readability wins. I do not believe that there is a lot to gain from overflow protection given the numbers used in these calculations are very small (and many are already bounds checked in some form or other). Well, I had to ask. Here is option 2. Index: bootstrap.c === RCS file: /cvs/src/usr.sbin/installboot/bootstrap.c,v retrieving revision 1.3 diff -u -p -r1.3 bootstrap.c --- bootstrap.c 28 Dec 2013 12:01:33 - 1.3 +++ bootstrap.c 31 May 2014 18:14:56 - @@ -68,10 +68,9 @@ bootstrap(int devfd, char *dev, char *bo fprintf(stderr, bootstrap is %zu bytes (%zu sectors @ %u bytes = %zu bytes)\n, (ssize_t)sb.st_size, bootsec, dl.d_secsize, bootsize); - boot = malloc(bootsize); + boot = calloc(1, bootsize); if (boot == NULL) - err(1, malloc); - memset(boot, 0, bootsize); + err(1, calloc); if (read(fd, boot, bootsize) != (ssize_t)sb.st_size) err(1, read); close(fd); Index: i386_softraid.c === RCS file: /cvs/src/usr.sbin/installboot/i386_softraid.c,v retrieving revision 1.1 diff -u -p -r1.1 i386_softraid.c --- i386_softraid.c 19 Jan 2014 02:58:50 - 1.1 +++ i386_softraid.c 31 May 2014 18:14:56 - @@ -129,11 +129,10 @@ sr_install_bootldr(int devfd, char *dev) inodeblk = nblocks - 1; bootsize = nblocks * SR_FS_BLOCKSIZE; - p = malloc(bootsize); + p = calloc(1, bootsize); if (p == NULL) err(1, NULL); - memset(p, 0, bootsize); fd = open(stage2, O_RDONLY, 0); if (fd == -1) err(1, NULL); Index: sparc64_installboot.c === RCS file: /cvs/src/usr.sbin/installboot/sparc64_installboot.c,v retrieving revision 1.1 diff -u -p -r1.1 sparc64_installboot.c --- sparc64_installboot.c 19 Jan 2014 02:58:50 - 1.1 +++ sparc64_installboot.c 31 May 2014 18:14:56 - @@ -68,10 +68,9 @@ md_loadboot(void) if (blksize SBSIZE - DEV_BSIZE) errx(1, boot blocks too big (%zu %d), blksize, SBSIZE - DEV_BSIZE); - blkstore = malloc(blksize); + blkstore = calloc(1, blksize); if (blkstore == NULL) - err(1, malloc); - memset(blkstore, 0, blksize); + err(1, calloc); if (read(fd, blkstore, sb.st_size) != (ssize_t)sb.st_size) err(1, read); close(fd);
