Improve file API

Prefix function names and improve documentation.

app/meson.build

@@ -24,6 +24,7 @@ src = [
     'src/server.c',
     'src/stream.c',
     'src/video_buffer.c',
+    'src/util/file.c',
     'src/util/log.c',
     'src/util/net.c',
     'src/util/process.c',
@@ -35,9 +36,15 @@ src = [
 ]
 
 if host_machine.system() == 'windows'
-    src += [ 'src/sys/win/process.c' ]
+    src += [
+        'src/sys/win/file.c',
+        'src/sys/win/process.c',
+    ]
 else
-    src += [ 'src/sys/unix/process.c' ]
+    src += [
+        'src/sys/unix/file.c',
+        'src/sys/unix/process.c',
+    ]
 endif
 
 v4l2_support = host_machine.system() == 'linux'

app/src/adb.c

@@ -5,6 +5,7 @@
 #include <stdlib.h>
 #include <string.h>
 
+#include "util/file.h"
 #include "util/log.h"
 #include "util/str_util.h"
 
@@ -68,7 +69,7 @@ show_adb_installation_msg() {
         {"pacman", "pacman -S android-tools"},
     };
     for (size_t i = 0; i < ARRAY_LEN(pkg_managers); ++i) {
-        if (search_executable(pkg_managers[i].binary)) {
+        if (sc_file_executable_exists(pkg_managers[i].binary)) {
             LOGI("You may install 'adb' by \"%s\"", pkg_managers[i].command);
             return;
         }

app/src/icon.c

@@ -8,8 +8,8 @@
 
 #include "config.h"
 #include "compat.h"
+#include "util/file.h"
 #include "util/log.h"
-#include "util/process.h"
 #include "util/str_util.h"
 
 #define SCRCPY_PORTABLE_ICON_FILENAME "icon.png"
@@ -46,7 +46,7 @@ get_icon_path(void) {
         return NULL;
     }
 #else
-    char *icon_path = get_local_file_path(SCRCPY_PORTABLE_ICON_FILENAME);
+    char *icon_path = sc_file_get_local_path(SCRCPY_PORTABLE_ICON_FILENAME);
     if (!icon_path) {
         LOGE("Could not get icon path");
         return NULL;

app/src/server.c

@@ -8,6 +8,7 @@
 #include <SDL2/SDL_platform.h>
 
 #include "adb.h"
+#include "util/file.h"
 #include "util/log.h"
 #include "util/net.h"
 #include "util/str_util.h"
@@ -48,7 +49,7 @@ get_server_path(void) {
         return NULL;
     }
 #else
-    char *server_path = get_local_file_path(SERVER_FILENAME);
+    char *server_path = sc_file_get_local_path(SERVER_FILENAME);
     if (!server_path) {
         LOGE("Could not get local file path, "
              "using " SERVER_FILENAME " from current directory");
@@ -67,7 +68,7 @@ push_server(const char *serial) {
     if (!server_path) {
         return false;
     }
-    if (!is_regular_file(server_path)) {
+    if (!sc_file_is_regular(server_path)) {
         LOGE("'%s' does not exist or is not a regular file\n", server_path);
         free(server_path);
         return false;

app/src/sys/unix/file.c

@@ -0,0 +1,75 @@
+#include "util/file.h"
+
+#include <limits.h>
+#include <stdlib.h>
+#include <string.h>
+#include <sys/stat.h>
+#include <unistd.h>
+
+bool
+sc_file_executable_exists(const char *file) {
+    char *path = getenv("PATH");
+    if (!path)
+        return false;
+    path = strdup(path);
+    if (!path)
+        return false;
+
+    bool ret = false;
+    size_t file_len = strlen(file);
+    char *saveptr;
+    for (char *dir = strtok_r(path, ":", &saveptr); dir;
+            dir = strtok_r(NULL, ":", &saveptr)) {
+        size_t dir_len = strlen(dir);
+        char *fullpath = malloc(dir_len + file_len + 2);
+        if (!fullpath)
+            continue;
+        memcpy(fullpath, dir, dir_len);
+        fullpath[dir_len] = '/';
+        memcpy(fullpath + dir_len + 1, file, file_len + 1);
+
+        struct stat sb;
+        bool fullpath_executable = stat(fullpath, &sb) == 0 &&
+            sb.st_mode & S_IXUSR;
+        free(fullpath);
+        if (fullpath_executable) {
+            ret = true;
+            break;
+        }
+    }
+
+    free(path);
+    return ret;
+}
+
+char *
+sc_file_get_executable_path(void) {
+// <https://stackoverflow.com/a/1024937/1987178>
+#ifdef __linux__
+    char buf[PATH_MAX + 1]; // +1 for the null byte
+    ssize_t len = readlink("/proc/self/exe", buf, PATH_MAX);
+    if (len == -1) {
+        perror("readlink");
+        return NULL;
+    }
+    buf[len] = '\0';
+    return strdup(buf);
+#else
+    // in practice, we only need this feature for portable builds, only used on
+    // Windows, so we don't care implementing it for every platform
+    // (it's useful to have a working version on Linux for debugging though)
+    return NULL;
+#endif
+}
+
+bool
+sc_file_is_regular(const char *path) {
+    struct stat path_stat;
+
+    if (stat(path, &path_stat)) {
+        perror("stat");
+        return false;
+    }
+    return S_ISREG(path_stat.st_mode);
+}
+

app/src/sys/unix/process.c

@@ -3,53 +3,13 @@
 #include <assert.h>
 #include <errno.h>
 #include <fcntl.h>
-#include <limits.h>
 #include <signal.h>
-#include <stdlib.h>
-#include <string.h>
-#include <sys/stat.h>
 #include <sys/types.h>
 #include <sys/wait.h>
 #include <unistd.h>
 
 #include "util/log.h"
 
-bool
-search_executable(const char *file) {
-    char *path = getenv("PATH");
-    if (!path)
-        return false;
-    path = strdup(path);
-    if (!path)
-        return false;
-
-    bool ret = false;
-    size_t file_len = strlen(file);
-    char *saveptr;
-    for (char *dir = strtok_r(path, ":", &saveptr); dir;
-            dir = strtok_r(NULL, ":", &saveptr)) {
-        size_t dir_len = strlen(dir);
-        char *fullpath = malloc(dir_len + file_len + 2);
-        if (!fullpath)
-            continue;
-        memcpy(fullpath, dir, dir_len);
-        fullpath[dir_len] = '/';
-        memcpy(fullpath + dir_len + 1, file, file_len + 1);
-
-        struct stat sb;
-        bool fullpath_executable = stat(fullpath, &sb) == 0 &&
-            sb.st_mode & S_IXUSR;
-        free(fullpath);
-        if (fullpath_executable) {
-            ret = true;
-            break;
-        }
-    }
-
-    free(path);
-    return ret;
-}
-
 enum process_result
 process_execute_redirect(const char *const argv[], pid_t *pid, int *pipe_stdin,
                      int *pipe_stdout, int *pipe_stderr) {
@@ -232,37 +192,6 @@ process_close(pid_t pid) {
     process_wait(pid, true); // ignore exit code
 }
 
-char *
-get_executable_path(void) {
-// <https://stackoverflow.com/a/1024937/1987178>
-#ifdef __linux__
-    char buf[PATH_MAX + 1]; // +1 for the null byte
-    ssize_t len = readlink("/proc/self/exe", buf, PATH_MAX);
-    if (len == -1) {
-        perror("readlink");
-        return NULL;
-    }
-    buf[len] = '\0';
-    return strdup(buf);
-#else
-    // in practice, we only need this feature for portable builds, only used on
-    // Windows, so we don't care implementing it for every platform
-    // (it's useful to have a working version on Linux for debugging though)
-    return NULL;
-#endif
-}
-
-bool
-is_regular_file(const char *path) {
-    struct stat path_stat;
-
-    if (stat(path, &path_stat)) {
-        perror("stat");
-        return false;
-    }
-    return S_ISREG(path_stat.st_mode);
-}
-
 ssize_t
 read_pipe(int pipe, char *data, size_t len) {
     return read(pipe, data, len);

app/src/sys/win/file.c

@@ -0,0 +1,43 @@
+#include "util/file.h"
+
+#include <windows.h>
+
+#include <sys/stat.h>
+
+#include "util/log.h"
+#include "util/str_util.h"
+
+char *
+sc_file_get_executable_path(void) {
+    HMODULE hModule = GetModuleHandleW(NULL);
+    if (!hModule) {
+        return NULL;
+    }
+    WCHAR buf[MAX_PATH + 1]; // +1 for the null byte
+    int len = GetModuleFileNameW(hModule, buf, MAX_PATH);
+    if (!len) {
+        return NULL;
+    }
+    buf[len] = '\0';
+    return utf8_from_wide_char(buf);
+}
+
+bool
+sc_file_is_regular(const char *path) {
+    wchar_t *wide_path = utf8_to_wide_char(path);
+    if (!wide_path) {
+        LOGC("Could not allocate wide char string");
+        return false;
+    }
+
+    struct _stat path_stat;
+    int r = _wstat(wide_path, &path_stat);
+    free(wide_path);
+
+    if (r) {
+        perror("stat");
+        return false;
+    }
+    return S_ISREG(path_stat.st_mode);
+}
+

app/src/sys/win/process.c

@@ -1,7 +1,6 @@
 #include "util/process.h"
 
 #include <assert.h>
-#include <sys/stat.h>
 
 #include "util/log.h"
 #include "util/str_util.h"
@@ -174,40 +173,6 @@ process_close(HANDLE handle) {
     (void) closed;
 }
 
-char *
-get_executable_path(void) {
-    HMODULE hModule = GetModuleHandleW(NULL);
-    if (!hModule) {
-        return NULL;
-    }
-    WCHAR buf[MAX_PATH + 1]; // +1 for the null byte
-    int len = GetModuleFileNameW(hModule, buf, MAX_PATH);
-    if (!len) {
-        return NULL;
-    }
-    buf[len] = '\0';
-    return utf8_from_wide_char(buf);
-}
-
-bool
-is_regular_file(const char *path) {
-    wchar_t *wide_path = utf8_to_wide_char(path);
-    if (!wide_path) {
-        LOGC("Could not allocate wide char string");
-        return false;
-    }
-
-    struct _stat path_stat;
-    int r = _wstat(wide_path, &path_stat);
-    free(wide_path);
-
-    if (r) {
-        perror("stat");
-        return false;
-    }
-    return S_ISREG(path_stat.st_mode);
-}
-
 ssize_t
 read_pipe(HANDLE pipe, char *data, size_t len) {
     DWORD r;

app/src/util/file.c

@@ -0,0 +1,48 @@
+#include "file.h"
+
+#include <stdlib.h>
+#include <string.h>
+
+#include "util/log.h"
+
+char *
+sc_file_get_local_path(const char *name) {
+    char *executable_path = sc_file_get_executable_path();
+    if (!executable_path) {
+        return NULL;
+    }
+
+    // dirname() does not work correctly everywhere, so get the parent
+    // directory manually.
+    // See <https://github.com/Genymobile/scrcpy/issues/2619>
+    char *p = strrchr(executable_path, SC_PATH_SEPARATOR);
+    if (!p) {
+        LOGE("Unexpected executable path: \"%s\" (it should contain a '%c')",
+             executable_path, SC_PATH_SEPARATOR);
+        free(executable_path);
+        return NULL;
+    }
+
+    *p = '\0'; // modify executable_path in place
+    char *dir = executable_path;
+    size_t dirlen = strlen(dir);
+    size_t namelen = strlen(name);
+
+    size_t len = dirlen + namelen + 2; // +2: '/' and '\0'
+    char *file_path = malloc(len);
+    if (!file_path) {
+        LOGE("Could not alloc path");
+        free(executable_path);
+        return NULL;
+    }
+
+    memcpy(file_path, dir, dirlen);
+    file_path[dirlen] = SC_PATH_SEPARATOR;
+    // namelen + 1 to copy the final '\0'
+    memcpy(&file_path[dirlen + 1], name, namelen + 1);
+
+    free(executable_path);
+
+    return file_path;
+}
+

app/src/util/file.h

@@ -0,0 +1,49 @@
+#ifndef SC_FILE_H
+#define SC_FILE_H
+
+#include "common.h"
+
+#include <stdbool.h>
+
+#ifdef _WIN32
+# define SC_PATH_SEPARATOR '\\'
+#else
+# define SC_PATH_SEPARATOR '/'
+#endif
+
+#ifndef _WIN32
+/**
+ * Indicate if an executable exists using $PATH
+ *
+ * In practice, it is only used to know if a package manager is available on
+ * the system. It is only implemented on Linux.
+ */
+bool
+sc_file_executable_exists(const char *file);
+#endif
+
+/**
+ * Return the absolute path of the executable (the scrcpy binary)
+ *
+ * The result must be freed by the caller using free(). It may return NULL on
+ * error.
+ */
+char *
+sc_file_get_executable_path(void);
+
+/**
+ * Return the absolute path of a file in the same directory as the executable
+ *
+ * The result must be freed by the caller using free(). It may return NULL on
+ * error.
+ */
+char *
+sc_file_get_local_path(const char *name);
+
+/**
+ * Indicate if the file exists and is not a directory
+ */
+bool
+sc_file_is_regular(const char *path);
+
+#endif

app/src/util/process.c

@@ -21,47 +21,6 @@ process_check_success(process_t proc, const char *name, bool close) {
     return true;
 }
 
-char *
-get_local_file_path(const char *name) {
-    char *executable_path = get_executable_path();
-    if (!executable_path) {
-        return NULL;
-    }
-
-    // dirname() does not work correctly everywhere, so get the parent
-    // directory manually.
-    // See <https://github.com/Genymobile/scrcpy/issues/2619>
-    char *p = strrchr(executable_path, PATH_SEPARATOR);
-    if (!p) {
-        LOGE("Unexpected executable path: \"%s\" (it should contain a '%c')",
-             executable_path, PATH_SEPARATOR);
-        free(executable_path);
-        return NULL;
-    }
-
-    *p = '\0'; // modify executable_path in place
-    char *dir = executable_path;
-    size_t dirlen = strlen(dir);
-    size_t namelen = strlen(name);
-
-    size_t len = dirlen + namelen + 2; // +2: '/' and '\0'
-    char *file_path = malloc(len);
-    if (!file_path) {
-        LOGE("Could not alloc path");
-        free(executable_path);
-        return NULL;
-    }
-
-    memcpy(file_path, dir, dirlen);
-    file_path[dirlen] = PATH_SEPARATOR;
-    // namelen + 1 to copy the final '\0'
-    memcpy(&file_path[dirlen + 1], name, namelen + 1);
-
-    free(executable_path);
-
-    return file_path;
-}
-
 ssize_t
 read_pipe_all(pipe_t pipe, char *data, size_t len) {
     size_t copied = 0;

app/src/util/process.h

@@ -10,7 +10,6 @@
  // not needed here, but winsock2.h must never be included AFTER windows.h
 # include <winsock2.h>
 # include <windows.h>
-# define PATH_SEPARATOR '\\'
 # define PRIexitcode "lu"
 // <https://stackoverflow.com/a/44383330/1987178>
 # define PRIsizet "Iu"
@@ -23,7 +22,6 @@
 #else
 
 # include <sys/types.h>
-# define PATH_SEPARATOR '/'
 # define PRIsizet "zu"
 # define PRIexitcode "d"
 # define PROCESS_NONE -1
@@ -73,26 +71,6 @@ process_close(process_t pid);
 bool
 process_check_success(process_t proc, const char *name, bool close);
 
-#ifndef _WIN32
-// only used to find package manager, not implemented for Windows
-bool
-search_executable(const char *file);
-#endif
-
-// return the absolute path of the executable (the scrcpy binary)
-// may be NULL on error; to be freed by free()
-char *
-get_executable_path(void);
-
-// Return the absolute path of a file in the same directory as he executable.
-// May be NULL on error. To be freed by free().
-char *
-get_local_file_path(const char *name);
-
-// returns true if the file exists and is not a directory
-bool
-is_regular_file(const char *path);
-
 ssize_t
 read_pipe(pipe_t pipe, char *data, size_t len);