]> sigrok.org Git - libserialport.git/blobdiff - linux.c
change type of result variables to ssize_t
[libserialport.git] / linux.c
diff --git a/linux.c b/linux.c
index 8e9bfbf72ccbd1c46e4d0511020eb9f0f11421ed..8f320859dc91b329caf6688a3e250ad371b6a5d5 100644 (file)
--- a/linux.c
+++ b/linux.c
@@ -1,6 +1,7 @@
 /*
  * This file is part of the libserialport project.
  *
+ * Copyright (C) 2013 Martin Ling <martin-libserialport@earth.li>
  * Copyright (C) 2014 Aurelien Jacobs <aurel@gnuage.org>
  *
  * This program is free software: you can redistribute it and/or modify
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
 
+#include <config.h>
 #include "libserialport.h"
 #include "libserialport_internal.h"
 
+/*
+ * The 'e' modifier for O_CLOEXEC is glibc >= 2.7 only, hence not
+ * portable, so provide an own wrapper for this functionality.
+ */
+static FILE *fopen_cloexec_rdonly(const char *pathname)
+{
+       int fd;
+       if ((fd = open(pathname, O_RDONLY | O_CLOEXEC)) < 0)
+               return NULL;
+       return fdopen(fd, "r");
+}
+
 SP_PRIV enum sp_return get_port_details(struct sp_port *port)
 {
-       /* Description limited to 127 char,
-          anything longer would not be user friendly anyway */
+       /*
+        * Description limited to 127 char, anything longer
+        * would not be user friendly anyway.
+        */
        char description[128];
        int bus, address;
        unsigned int vid, pid;
        char manufacturer[128], product[128], serial[128];
        char baddr[32];
        const char dir_name[] = "/sys/class/tty/%s/device/%s%s";
-       char sub_dir[32] = "", file_name[PATH_MAX];
+       char sub_dir[32] = "", link_name[PATH_MAX], file_name[PATH_MAX];
        char *ptr, *dev = port->name + 5;
        FILE *file;
        int i, count;
+       struct stat statbuf;
 
        if (strncmp(port->name, "/dev/", 5))
-               RETURN_ERROR(SP_ERR_ARG, "Device name not recognized.");
+               RETURN_ERROR(SP_ERR_ARG, "Device name not recognized");
 
-       snprintf(file_name, sizeof(file_name), "/sys/class/tty/%s", dev);
-       count = readlink(file_name, file_name, sizeof(file_name));
-       if (count <= 0 || count >= (int) sizeof(file_name)-1)
-               RETURN_ERROR(SP_ERR_ARG, "Device not found.");
+       snprintf(link_name, sizeof(link_name), "/sys/class/tty/%s", dev);
+       if (lstat(link_name, &statbuf) == -1)
+               RETURN_ERROR(SP_ERR_ARG, "Device not found");
+       if (!S_ISLNK(statbuf.st_mode))
+               snprintf(link_name, sizeof(link_name), "/sys/class/tty/%s/device", dev);
+       count = readlink(link_name, file_name, sizeof(file_name));
+       if (count <= 0 || count >= (int)(sizeof(file_name) - 1))
+               RETURN_ERROR(SP_ERR_ARG, "Device not found");
        file_name[count] = 0;
        if (strstr(file_name, "bluetooth"))
                port->transport = SP_TRANSPORT_BLUETOOTH;
@@ -49,11 +70,11 @@ SP_PRIV enum sp_return get_port_details(struct sp_port *port)
                port->transport = SP_TRANSPORT_USB;
 
        if (port->transport == SP_TRANSPORT_USB) {
-               for (i=0; i<5; i++) {
+               for (i = 0; i < 5; i++) {
                        strcat(sub_dir, "../");
 
                        snprintf(file_name, sizeof(file_name), dir_name, dev, sub_dir, "busnum");
-                       if (!(file = fopen(file_name, "r")))
+                       if (!(file = fopen_cloexec_rdonly(file_name)))
                                continue;
                        count = fscanf(file, "%d", &bus);
                        fclose(file);
@@ -61,7 +82,7 @@ SP_PRIV enum sp_return get_port_details(struct sp_port *port)
                                continue;
 
                        snprintf(file_name, sizeof(file_name), dir_name, dev, sub_dir, "devnum");
-                       if (!(file = fopen(file_name, "r")))
+                       if (!(file = fopen_cloexec_rdonly(file_name)))
                                continue;
                        count = fscanf(file, "%d", &address);
                        fclose(file);
@@ -69,7 +90,7 @@ SP_PRIV enum sp_return get_port_details(struct sp_port *port)
                                continue;
 
                        snprintf(file_name, sizeof(file_name), dir_name, dev, sub_dir, "idVendor");
-                       if (!(file = fopen(file_name, "r")))
+                       if (!(file = fopen_cloexec_rdonly(file_name)))
                                continue;
                        count = fscanf(file, "%4x", &vid);
                        fclose(file);
@@ -77,7 +98,7 @@ SP_PRIV enum sp_return get_port_details(struct sp_port *port)
                                continue;
 
                        snprintf(file_name, sizeof(file_name), dir_name, dev, sub_dir, "idProduct");
-                       if (!(file = fopen(file_name, "r")))
+                       if (!(file = fopen_cloexec_rdonly(file_name)))
                                continue;
                        count = fscanf(file, "%4x", &pid);
                        fclose(file);
@@ -90,7 +111,7 @@ SP_PRIV enum sp_return get_port_details(struct sp_port *port)
                        port->usb_pid = pid;
 
                        snprintf(file_name, sizeof(file_name), dir_name, dev, sub_dir, "product");
-                       if ((file = fopen(file_name, "r"))) {
+                       if ((file = fopen_cloexec_rdonly(file_name))) {
                                if ((ptr = fgets(description, sizeof(description), file))) {
                                        ptr = description + strlen(description) - 1;
                                        if (ptr >= description && *ptr == '\n')
@@ -103,7 +124,7 @@ SP_PRIV enum sp_return get_port_details(struct sp_port *port)
                                port->description = strdup(dev);
 
                        snprintf(file_name, sizeof(file_name), dir_name, dev, sub_dir, "manufacturer");
-                       if ((file = fopen(file_name, "r"))) {
+                       if ((file = fopen_cloexec_rdonly(file_name))) {
                                if ((ptr = fgets(manufacturer, sizeof(manufacturer), file))) {
                                        ptr = manufacturer + strlen(manufacturer) - 1;
                                        if (ptr >= manufacturer && *ptr == '\n')
@@ -114,7 +135,7 @@ SP_PRIV enum sp_return get_port_details(struct sp_port *port)
                        }
 
                        snprintf(file_name, sizeof(file_name), dir_name, dev, sub_dir, "product");
-                       if ((file = fopen(file_name, "r"))) {
+                       if ((file = fopen_cloexec_rdonly(file_name))) {
                                if ((ptr = fgets(product, sizeof(product), file))) {
                                        ptr = product + strlen(product) - 1;
                                        if (ptr >= product && *ptr == '\n')
@@ -125,7 +146,7 @@ SP_PRIV enum sp_return get_port_details(struct sp_port *port)
                        }
 
                        snprintf(file_name, sizeof(file_name), dir_name, dev, sub_dir, "serial");
-                       if ((file = fopen(file_name, "r"))) {
+                       if ((file = fopen_cloexec_rdonly(file_name))) {
                                if ((ptr = fgets(serial, sizeof(serial), file))) {
                                        ptr = serial + strlen(serial) - 1;
                                        if (ptr >= serial && *ptr == '\n')
@@ -151,7 +172,7 @@ SP_PRIV enum sp_return get_port_details(struct sp_port *port)
 
                if (port->transport == SP_TRANSPORT_BLUETOOTH) {
                        snprintf(file_name, sizeof(file_name), dir_name, dev, "", "address");
-                       if ((file = fopen(file_name, "r"))) {
+                       if ((file = fopen_cloexec_rdonly(file_name))) {
                                if ((ptr = fgets(baddr, sizeof(baddr), file))) {
                                        ptr = baddr + strlen(baddr) - 1;
                                        if (ptr >= baddr && *ptr == '\n')
@@ -169,59 +190,66 @@ SP_PRIV enum sp_return get_port_details(struct sp_port *port)
 SP_PRIV enum sp_return list_ports(struct sp_port ***list)
 {
        char name[PATH_MAX], target[PATH_MAX];
-       struct dirent entry, *result;
-#ifdef HAVE_SERIAL_STRUCT
+       struct dirent *entry;
+#ifdef HAVE_STRUCT_SERIAL_STRUCT
        struct serial_struct serial_info;
        int ioctl_result;
 #endif
-       char buf[sizeof(entry.d_name) + 16];
+       char buf[sizeof(entry->d_name) + 23];
        int len, fd;
        DIR *dir;
        int ret = SP_OK;
+       struct stat statbuf;
 
        DEBUG("Enumerating tty devices");
        if (!(dir = opendir("/sys/class/tty")))
-               RETURN_FAIL("could not open /sys/class/tty");
+               RETURN_FAIL("Could not open /sys/class/tty");
 
        DEBUG("Iterating over results");
-       while (!readdir_r(dir, &entry, &result) && result) {
-               snprintf(buf, sizeof(buf), "/sys/class/tty/%s", entry.d_name);
+       while ((entry = readdir(dir))) {
+               snprintf(buf, sizeof(buf), "/sys/class/tty/%s", entry->d_name);
+               if (lstat(buf, &statbuf) == -1)
+                       continue;
+               if (!S_ISLNK(statbuf.st_mode))
+                       snprintf(buf, sizeof(buf), "/sys/class/tty/%s/device", entry->d_name);
                len = readlink(buf, target, sizeof(target));
-               if (len <= 0 || len >= (int) sizeof(target)-1)
+               if (len <= 0 || len >= (int)(sizeof(target) - 1))
                        continue;
                target[len] = 0;
                if (strstr(target, "virtual"))
                        continue;
-               snprintf(name, sizeof(name), "/dev/%s", entry.d_name);
+               snprintf(name, sizeof(name), "/dev/%s", entry->d_name);
                DEBUG_FMT("Found device %s", name);
                if (strstr(target, "serial8250")) {
-                       /* The serial8250 driver has a hardcoded number of ports.
+                       /*
+                        * The serial8250 driver has a hardcoded number of ports.
                         * The only way to tell which actually exist on a given system
-                        * is to try to open them and make an ioctl call. */
+                        * is to try to open them and make an ioctl call.
+                        */
                        DEBUG("serial8250 device, attempting to open");
-                       if ((fd = open(name, O_RDWR | O_NONBLOCK | O_NOCTTY)) < 0) {
-                               DEBUG("open failed, skipping");
+                       if ((fd = open(name, O_RDWR | O_NONBLOCK | O_NOCTTY | O_CLOEXEC)) < 0) {
+                               DEBUG("Open failed, skipping");
                                continue;
                        }
-#ifdef HAVE_SERIAL_STRUCT
+#ifdef HAVE_STRUCT_SERIAL_STRUCT
                        ioctl_result = ioctl(fd, TIOCGSERIAL, &serial_info);
 #endif
                        close(fd);
-#ifdef HAVE_SERIAL_STRUCT
+#ifdef HAVE_STRUCT_SERIAL_STRUCT
                        if (ioctl_result != 0) {
                                DEBUG("ioctl failed, skipping");
                                continue;
                        }
                        if (serial_info.type == PORT_UNKNOWN) {
-                               DEBUG("port type is unknown, skipping");
+                               DEBUG("Port type is unknown, skipping");
                                continue;
                        }
 #endif
                }
                DEBUG_FMT("Found port %s", name);
                *list = list_append(*list, name);
-               if (!list) {
-                       SET_ERROR(ret, SP_ERR_MEM, "list append failed");
+               if (!*list) {
+                       SET_ERROR(ret, SP_ERR_MEM, "List append failed");
                        break;
                }
        }